Method of wiring layout, semiconductor device, program for supporting design of wiring layout, and method for manufacturing semiconductor device

ABSTRACT

According to one embodiment, a design method of layout formed by a sidewall method is provided. The method includes: preparing a base pattern on which a plurality of first patterns extending in a first direction and arranged at a first space in a second direction intersecting the first direction and a plurality of second patterns extending in the first direction and arranged at a center between the first patterns, respectively, are provided; and drawing a connecting portion which extends in the second direction and connects two neighboring first patterns sandwiching one of the second patterns, and separating the one of the second patterns into two patterns not contacting the connecting portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Continuation-in-Part application of application Ser. No.14/156,309, filed on Jan. 15, 2014; the entire contents of which areincorporated herein by reference.

This application is based upon and claims the benefit of priority fromthe prior Japanese Patent Application No. 2011-201230, filed on Sep. 14,2011; the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a design method ofwiring layout, a semiconductor device, a program for supporting designof wiring layout, and a method for manufacturing semiconductor device.

BACKGROUND

Double patterning is technology for exposing a circuit pattern of whichhas advanced beyond the resolution of lithography technology by dividingthe circuit pattern into two circuit patterns that fall within the rangeof the resolution of lithography technology.

On the other hand, it is possible to deem patterning technology by asidewall as one kind of double patterning. Hereinafter, this issometimes referred to as a “sidewall method”. The patterning technologyby a sidewall is a technique for forming a pattern using a sidewallformed on the side face of a mandrel as a mask.

However, the double patterning technology by a sidewall does not permitan H-shaped wiring pattern (stitch pattern), and therefore, the degreeof freedom in a design of a wiring layout is low.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a plan view illustrating a base pattern used in the designmethod of a wiring layout according to a first embodiment;

FIG. 1B shows an XY rectangular coordinate system adopted in FIG. 1A;

FIGS. 2A and 2B are plan views illustrating layout parts used in thefirst embodiment, wherein FIG. 2A shows a line-cutting part and FIG. 2Bshows a bridge part;

FIG. 2C shows an XY rectangular coordinate system adopted in FIGS. 2Aand 2B;

FIG. 3A is a plan view illustrating a state where the bridge parts andline-cutting parts are arranged on the base pattern in the firstembodiment;

FIG. 3B shows an XY rectangular coordinate system adopted in FIG. 3A;

FIG. 4A is a plan view illustrating a state where the pattern and bridgepart are classified by two colors in the first embodiment;

FIG. 4B shows an XY rectangular coordinate system adopted in FIG. 4A;

FIGS. 5A to 5C are process plan views illustrating a method formanufacturing a pattern by the sidewall method according to the firstembodiment and FIGS. 5D to 5F are process section views along A-A′ planeshown in FIGS. 5A to 5C, respectively;

FIGS. 6A to 6C are process plan views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern connecting between neighboring sidewalls;

FIG. 6D shows an XY rectangular coordinate system adopted in FIGS. 6A to6C;

FIGS. 7A to 7C are process section views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern connecting neighboring mandrels;

FIG. 7D shows an XY rectangular coordinate system adopted in FIGS. 7A to7C;

FIGS. 8A to 8C are process plan views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern between separated sidewalls;

FIG. 8D shows an XY rectangular coordinate system adopted in FIGS. 8A to8C;

FIGS. 9A to 9C are process plan views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern of a separated mandrel;

FIG. 9D shows an XY rectangular coordinate system adopted in FIGS. 9A to9C;

FIG. 10 is a plan view illustrating a method for manufacturing asemiconductor device according to the first embodiment;

FIG. 11 is a plan view illustrating a method for manufacturing asemiconductor device according to the first embodiment;

FIG. 12 is a plan view illustrating a method for manufacturing asemiconductor device according to the first embodiment;

FIG. 13A is a plan view illustrating a method for manufacturing asemiconductor device according to the first embodiment;

FIG. 13B shows an XY rectangular coordinate system adopted in FIG. 13A;

FIG. 14A is a plan view illustrating a base pattern to be used in themethod for designing a wiring layout according to the second embodiment;

FIG. 14B shows an XY rectangular coordinate system adopted in FIG. 14A;

FIGS. 15A to 15D are plan views illustrating layout parts used in thesecond embodiment, wherein FIG. 15A illustrates a line-cutting part,FIG. 15B a Y bridge part, FIG. 15C an X bridge part, and FIG. 15D acontact fringe;

FIG. 16 is a plan view illustrating a state where the bridge parts arearranged on the base pattern in the second embodiment;

FIG. 17 is a plan view illustrating a base pattern according to amodified example of the second embodiment;

FIGS. 18A to 18D are plan views illustrating a method for manufacturinga semiconductor device according to the second embodiment;

FIG. 18E shows an XY rectangular coordinate system adopted in FIGS. 18Ato 18D;

FIG. 19A is a plan view illustrating a base pattern used in the methodfor designing a wiring layout according to the third embodiment;

FIG. 19B shows an XY rectangular coordinate system adopted in FIG. 19A;

FIGS. 20A to 20D are plan views illustrating layout parts used in thethird embodiment, wherein FIG. 20A shows a line-cutting part and FIGS.20B to 20D show bridge parts;

FIG. 20E shows an XY rectangular coordinate system adopted in FIGS. 20Ato 20D;

FIG. 21A is a plan view illustrating a state where the bridge parts andline-cutting parts are arranged on the base pattern;

FIG. 21B shows an XY rectangular coordinate system adopted in FIG. 21A;

FIG. 22A is a plan view illustrating a state where patterns and thebridge parts are classified by three colors in the third embodiment;

FIG. 22B shows an XY rectangular coordinate system adopted in FIG. 22A;

FIGS. 23A to 23D are process plan views illustrating a method formanufacturing patterns by the sidewall method according to the thirdembodiment and FIGS. 23E to 23H are process section views along B-B′surface shown in FIGS. 23A to 23D, respectively;

FIGS. 24A to 24C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 24D shows an XY rectangular coordinate system adopted in FIGS. 24Ato 24C;

FIGS. 25A to 25C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 25D shows an XY rectangular coordinate system adopted in FIGS. 25Ato 25C;

FIGS. 26A to 26C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 26D shows an XY rectangular coordinate system adopted in FIGS. 26Ato 26C;

FIGS. 27A to 27C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 27D shows an XY rectangular coordinate system adopted in FIGS. 27Ato 27C;

FIGS. 28A to 28C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 28D shows an XY rectangular coordinate system adopted in FIGS. 28Ato 28C;

FIGS. 29A to 29C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 29D shows an XY rectangular coordinate system adopted in FIGS. 29Ato 29C;

FIGS. 30A to 30C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 30D shows an XY rectangular coordinate system adopted in FIGS. 30Ato 30C;

FIGS. 31A to 31C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 31D shows an XY rectangular coordinate system adopted in FIGS. 31Ato 31C;

FIGS. 32A to 32C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 32D shows an XY rectangular coordinate system adopted in FIGS. 32Ato 32C;

FIGS. 33A to 33C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 33D shows an XY rectangular coordinate system adopted in FIGS. 33Ato 33C;

FIGS. 34A to 34C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 34D shows an XY rectangular coordinate system adopted in FIGS. 34Ato 34C;

FIGS. 35A to 35C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 35D shows an XY rectangular coordinate system adopted in FIGS. 35Ato 35C;

FIGS. 36A to 36C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 36D shows an XY rectangular coordinate system adopted in FIGS. 36Ato 36C;

FIGS. 37A to 37C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 37D shows an XY rectangular coordinate system adopted in FIGS. 37Ato 37C;

FIGS. 38A to 38C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 38D shows an XY rectangular coordinate system adopted in FIGS. 38Ato 38C;

FIGS. 39A to 39C are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment;

FIG. 39D shows an XY rectangular coordinate system adopted in FIGS. 39Ato 39C;

FIG. 40A is a plan view illustrating the semiconductor device accordingto the third embodiment;

FIG. 40B shows an XY rectangular coordinate system adopted in FIG. 40A

FIG. 41A is a plan view illustrating a base pattern used in the methodfor designing a wiring layout according to the fourth embodiment;

FIG. 41B shows an XY rectangular coordinate system adopted in FIG. 41A;

FIGS. 42A to 42H are plan views illustrating layout parts used in thefourth embodiment, wherein FIG. 42A shows a line-cutting part, FIGS.42B, 42D, and 42F show Y bridge parts, FIGS. 42C, 42E, and 42G show Xbridge parts, and FIG. 42H shows a contact fringe;

FIG. 42I shows an XY rectangular coordinate system adopted in FIGS. 42Ato 42H;

FIG. 43A is a plan view illustrating a state where the bridge parts andthe contact fringe are arranged on the base pattern in the fourthembodiment;

FIG. 43B shows an XY rectangular coordinate system adopted in FIG. 43A;

FIG. 44A is a plan view illustrating a base pattern in the modifiedexample of the fourth embodiment;

FIG. 44B shows an XY rectangular coordinate system adopted in FIG. 44A;

FIG. 45A is a plan view illustrating the method for manufacturing asemiconductor device according to the fourth embodiment;

FIG. 45B shows an XY rectangular coordinate system adopted in FIG. 45A;

FIGS. 46A to 46D are plan views illustrating constituent units of a basepattern in the fifth embodiment;

FIGS. 47A and 47B are plan views illustrating constituent units of thebase pattern in the fifth embodiment and FIG. 47C is a plan viewillustrating a wiring layout in the fifth embodiment;

FIG. 48 exemplarily shows a base pattern used in a sidewall method wheresidewall is formed n times;

FIG. 49 illustrates a display unit;

FIG. 50 is a flow chart illustrating a design method of a wiring layoutand a method for manufacturing a semiconductor device according to asixth embodiment;

FIG. 51A is a plan view illustrating a sidewall wiring grid used in thedesign method of the wiring layout according to the sixth embodiment,and FIG. 51B shows an XY rectangular coordinate system adopted in FIG.51A;

FIG. 52A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 52B showsan XY rectangular coordinate system adopted in FIG. 52A;

FIG. 53A is a plan view illustrating a pattern for trimming mask in thesixth embodiment, and FIG. 53B shows an XY rectangular coordinate systemadopted in FIG. 53A;

FIGS. 54A and 54B are process plan views illustrating a method forforming the trimming mask in the sixth embodiment;

FIG. 55A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 55B showsan XY rectangular coordinate system adopted in FIG. 55A;

FIG. 56A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 56B showsan XY rectangular coordinate system adopted in FIG. 56A;

FIGS. 57A to 57C are plan views illustrating a method for determining apreferred direction of a dummy wiring, and FIG. 57D shows an XYrectangular coordinate system adopted in FIGS. 57A to 57C;

FIG. 58A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 58B showsan XY rectangular coordinate system adopted in FIG. 58A;

FIG. 59A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 59B showsan XY rectangular coordinate system adopted in FIG. 59A;

FIG. 60A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid before changing a connection direction ofthe dummy wiring, and FIG. 60B a plan view illustrating a state in whicha wiring is drawn on the sidewall wiring grid after changing aconnection direction of the dummy wiring;

FIG. 61A is a process plan view illustrating a method for manufacturinga semiconductor device according to the sixth embodiment, and FIG. 61Bshows an XY rectangular coordinate system adopted in FIG. 61A;

FIGS. 62A to 62C are process sectional views illustrating the method formanufacturing the semiconductor device according to the sixthembodiment;

FIG. 63A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, and FIG. 63B shows an XY rectangular coordinate systemadopted in FIG. 63A;

FIGS. 64A to 64C are process sectional views illustrating the method formanufacturing the semiconductor device according to the sixthembodiment;

FIG. 65A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, FIG. 65B shows an XY rectangular coordinate system adoptedin FIG. 65A, and FIG. 65C is a process sectional view illustrating themethod for manufacturing the semiconductor device according to the sixthembodiment;

FIG. 66A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, and FIG. 66B shows an XY rectangular coordinate systemadopted in FIG. 66A;

FIG. 67A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, and FIG. 67B shows an XY rectangular coordinate systemadopted in FIG. 67A;

FIG. 68A is a plan view illustrating a sidewall wiring grid used in adesign method of a wiring layout according to a seventh embodiment, andFIG. 68B shows an XY rectangular coordinate system adopted in FIG. 68A;

FIG. 69A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 69B showsan XY rectangular coordinate system adopted in FIG. 69A;

FIG. 70A to FIG. 75B are plan views showing schematically a process of a2-time sidewall method;

FIG. 76A is a plan view illustrating a state in which a wiring is drawnon a sidewall wiring grid in a variation of the seventh embodiment, andFIG. 76B shows an XY rectangular coordinate system adopted in FIG. 76A;

FIG. 77 is a flow chart showing a method of mask design according to aneighth embodiment;

FIG. 78A to FIG. 81B are schematic plan views showing a rule of maskdesign according to the eighth embodiment;

FIG. 82A to FIG. 82C are plan views showing a method for extracting themandrel pattern;

FIG. 83 is a plan view illustrating a base grid according to theembodiment;

FIG. 84 and FIG. 85 are schematic plan views showing a process fordrawing a first wiring on the base grid;

FIG. 86 to FIG. 88 are plan views showing a process for drawing a secondwiring on the base grid;

FIG. 89 to FIG. 94 are schematic plan views showing a process fordrawing a subsequent first wiring 801 on the base grid;

FIG. 95 is a schematic plan view showing a process for drawing a thirdwiring and a fourth wiring on the base grid;

FIG. 96 and FIG. 97 are plan views showing a process for expanding thesecond wiring;

FIG. 98 is a plan view showing a state where a trim pattern is extractedfrom the base grid;

FIG. 99A to FIG. 99C are schematic plan views showing an extraction of amandrel pattern in the base grid;

FIGS. 100A to 101C are schematic plan views showing another rules of themask design;

FIGS. 102A and 104B are schematic plan views showing a rule of maskdesign according to a variation of the eighth embodiment;

FIGS. 105A and 105B are schematic views showing a mask designs accordingto the eighth embodiment; and

FIG. 106A to FIG. 108C are schematic plan views showing a manufacturingprocess of a semiconductor device according to the eighth embodiment.

FIG. 109A to FIG. 109C are schematic views illustrating examples of awiring layout according to a connection rule;

FIG. 110 to FIG. 113 are schematic views illustrating a design processof a wiring layout according to a ninth embodiment;

FIG. 114A to FIG. 115F are schematic plan views illustrating amanufacturing process of a semiconductor device according to a tenthembodiment;

FIG. 116 to FIG. 121 are schematic plan views illustrating a process ofmask design according to the tenth embodiment;

FIG. 122 to FIG. 127 are schematic plan views illustrating a process forforming a wiring mask in the manufacturing process according to thetenth embodiment;

FIG. 128 is a flow chart showing a method of mask design according to aneleventh embodiment;

FIG. 129 to FIG. 136 are schematic plan views illustrating a process ofmask design according to the eleventh embodiment;

FIG. 137A to FIG. 141B are schematic views illustrating a manufacturingprocess of a semiconductor device according to the eleventh embodiment;

FIG. 142A to FIG. 147 are schematic views showing a mask design methodaccording to a variation of the eleventh embodiment;

FIG. 148A to FIG. 150 are schematic views showing a mask design methodaccording to another variation of the eleventh embodiment; and

FIG. 151A to FIG. 153 are schematic views showing a mask design methodaccording to other variation of the eleventh embodiment.

DETAILED DESCRIPTION

In general, according to one embodiment, a design method of layoutformed by a sidewall method is provided. The method includes: preparinga base pattern on which a plurality of first patterns extending in afirst direction and arranged at a first space in a second directionintersecting the first direction and a plurality of second patternsextending in the first direction and arranged at a center between thefirst patterns, respectively, are provided; and drawing a connectingportion which extends in the second direction and connects twoneighboring first patterns sandwiching one of the second patterns, andseparating the one of the second patterns into two patterns notcontacting the connecting portion.

In general, according to another embodiment, a design method of layoutformed by a sidewall method includes: providing a base pattern on whicha plurality of first points arranged in a matrix at a second space in afirst direction and at a first space in a second direction intersectingthe first direction, and a plurality of second points arranged in amatrix at the second space in the first direction and at the first spacein the second direction, the second points being arranged at a spaceshifted by half the second space in the first direction with respect tothe first point and arranged at a space shifted by half the first spacein the second direction, are provided; arranging a first bridge partconnecting the two first points in a predetermined position between thetwo first points neighboring in the first direction; arranging a secondbridge part connecting the two second points in a predetermined positionbetween the two second points neighboring in the first direction;arranging a third bridge part connecting the two first points in apredetermined position between the two first points neighboring in thesecond direction; and arranging a fourth bridge part connecting the twosecond points in a predetermined position between the two second pointsneighboring in the second direction.

In general, according to another embodiment, a semiconductor deviceincludes: a semiconductor substrate; a plurality of first patternsextending in a first direction in a plane parallel to the top face ofthe semiconductor substrate; a plurality of second patterns extending inthe first direction in the plane; a third pattern extending in a seconddirection intersecting the first direction in the plane; and a fourthpattern extending in the second direction in the plane, when a pluralityof first lines extending in the first direction and arranged at a firstspace in the second direction are supposed in the plane and integersfrom one are assigned to the first lines in order from the end, thefirst patterns being arranged in the odd-numbered first lines, thesecond patterns being arranged in the even-numbered first lines, thethird pattern connecting the first patterns, the fourth patternconnecting the second patterns, and the first pattern and the thirdpattern, and the second pattern and the fourth pattern being separatedfrom each other.

In general, according to another embodiment, a semiconductor deviceincludes: a semiconductor substrate; a plurality of first patternsextending in a first direction in a plane parallel to the top face ofthe semiconductor substrate; a plurality of second patterns extending inthe first direction and arranged one by one between the first patternsin the plane; a plurality of third patterns extending in the firstdirection and arranged one by one between the first pattern and thesecond pattern in the plane; and a fourth pattern extending in thesecond direction in the plane, the fourth pattern connecting twoneighboring the first patterns, and the first pattern and the thirdpattern, and the second pattern and the third pattern being separatedfrom each other.

In general, according to another embodiment, a semiconductor deviceincludes: a semiconductor substrate; a plurality of first patternsextending in a first direction in a plane parallel to the top face ofthe semiconductor substrate; a plurality of second patterns extending inthe first direction in the plane; a plurality of third patternsextending in a second direction intersecting the first direction in theplane; and a plurality of fourth patterns extending in the seconddirection in the plane, when a plurality of first lines extending in thefirst direction and arranged at a first space in the second directionare supposed in the plane and integers from one are assigned to thefirst lines in order from the end, and when a plurality of third linesextending in the second direction, arranged at a second space in thefirst direction, and intersecting the first lines are supposed in theplane and integers from one are assigned to the third lines in orderfrom the end, the first patterns being arranged in the odd-numberedfirst lines, the second patterns being arranged in the even-numberedfirst lines, the third patterns being arranged in the odd-numbered thirdlines, the fourth patterns being arranged in the even-numbered thirdlines, at least one of the first patterns connecting with the thirdpattern, at least one of the second patterns connecting with the fourthpattern, and the first pattern and the third pattern, and the secondpattern and the fourth pattern being separated from each other.

In general, according to another embodiment, a program for supporting adesign of a layout formed by a sidewall method is provided. The programcauses a computer to execute: a procedure to display a base pattern onwhich a plurality of first patterns extending in a first direction andarranged at a first space in a second direction intersecting the firstdirection, and a plurality of second patterns extending in the firstdirection and arranged respectively at the center between the firstpatterns are provided on a display unit; and a procedure, when a firstbridge part extending in the second direction is arranged in apredetermined position between the two neighboring first patternssandwiching the one second pattern in the base pattern displayed on thedisplay unit via an input unit, to replace the one second pattern withtwo patterns sandwiching the first bridge part and not contacting thefirst bridge part as well as connecting the two first patterns.

In general, according to another embodiment, a program for supporting adesign of a wiring layout formed by a sidewall method is provided. Theprogram causes a computer to execute: a procedure to display a basepattern on which a plurality of first points arranged in a matrix at asecond space in a first direction and at a first space in a seconddirection intersecting the first direction, and a plurality of secondpoints arranged in a matrix at the second space in the first directionand at the first space in the second direction, the second points beingarranged at a space shifted by half the second space in the firstdirection with respect to the first point and at a space shifted by halfthe first space in the second direction are provided on a display unit;and a procedure, when a first bridge part extending in the firstdirection is arranged in a predetermined position between the two firstpoints neighboring in the first direction in the base pattern displayedon the display unit via an input unit, to connect the two first points.

In general, according to another embodiment, a method for manufacturinga semiconductor device includes: forming an insulating film on asemiconductor substrate; forming a mandrel on the insulating film;forming a sidewall on a side face of the mandrel; removing the mandrel;selectively removing the insulating film to form a concave portion byperforming etching using the sidewall as a mask; removing the sidewall;and embedding an electrically conductive material within the concaveportion, the mandrel being formed in a region corresponding to a firstpattern in a layout designed by a method including: preparing a basepattern on which a plurality of the first patterns extending in a firstdirection and arranged at a first space in a second directionintersecting the first direction and a plurality of second patternsextending in the first direction and arranged at a center between thefirst patterns, respectively, are provided; and replacing one of thesecond patterns with two patterns not contacting a connecting portionwhich extends the second direction and connects two neighboring firstpatterns sandwiching the one of the second patterns.

First Embodiment

Hereinafter, embodiments of the invention are explained with referenceto the drawings.

First, a design method of a wiring layout formed by the sidewall methodis explained.

FIG. 1 is a plan view illustrating a base pattern used in the designmethod of a wiring layout according to a first embodiment.

FIGS. 2A and 2B are plan views illustrating layout parts used in thefirst embodiment, wherein FIG. 2A shows a line-cutting part and FIG. 2Bshows a bridge part.

FIG. 3 is a plan view illustrating a state where the bridge parts andline-cutting parts are arranged on the base pattern in the firstembodiment.

FIG. 4 is a plan view illustrating a state where the pattern and bridgepart are classified by two colors in the first embodiment.

First, the base pattern, the line-cutting part, and the bridge part usedin the design method of a wiring layout according to the embodiment areexplained.

In the embodiment, a wiring layout is designed by arranging theline-cutting parts and bridge parts in arbitrary positions on the basepattern according to fixed rules.

A designer may design the wiring layout using, for example, an inputunit, a computer and a display unit shown in FIG. 49. That is, thedesigner can operate the computer and arrange line-cutting parts andbridge parts in arbitrary positions on the base pattern of the displayunit under the support of the computer.

As shown in FIG. 1, on a base pattern 10 according to the embodiment, aplurality of first patterns 11 extending in one direction and aplurality of second patterns 12 extending in the one direction areprovided. One end of the first pattern 11 is connected to a horizontalpattern 13 extending in a direction perpendicular to the one direction.

In the embodiment, in order to explain the base pattern 10, an XYrectangular coordinate system is adopted. In the XY rectangularcoordinate system, of the directions in which the first pattern 11 andthe second pattern 12 extend, the direction toward the horizontalpattern 13 is referred to as +Y direction and the opposite direction isreferred to as −Y direction. Of the directions perpendicular to thedirection in which the first pattern 11 and the second pattern 12extend, the direction 90 degrees rotated clockwise from the +Y directionis referred to as +X direction and the opposite direction is referred toas −X direction. The “+X direction” and the “−X direction” are togetherreferred to also as “X direction”. The “+Y direction” and the “−Ydirection” are together referred to also as “Y direction”. In each ofthe drawings to be described later, the same XY rectangular coordinatesystem is used according to the necessity.

The first patterns 11 extend in the Y direction and are arranged at afixed space (hereinafter, referred to as the “first space”) in the Xdirection.

The second patterns 12 extend in the Y direction and arranged one by onesubstantially at the center between the first patterns. Consequently,the second patterns are arranged at the first space in the X direction.A distance between the first pattern 11 and the second pattern 12 isconstant. The width of each of the first pattern 11 and the secondpattern 12 can vary as long as the distance between the first pattern 11and the second pattern 12 is kept constant.

In the embodiment, the width of the first pattern 11 and the secondpattern 12 is set to a length ¼ of the first space. This width isreferred to as “length a”. The “length a” is a value that variesdepending on the process conditions. For example, when the minimumprocessing dimension of lithography is 20 nm, the length “a” is about 10nm.

As shown in FIG. 2A, a line-cutting part 14 includes a rectangularportion 15. The rectangular portion 15 is formed into the shape of asquare the side of which in the longitudinal and transverse directionsis equal to the width of the first pattern 11 and the second pattern 12,that is, the length a. Around the rectangular portion 15, a BOX region16 is set. The BOX region 16 is set so that the width is ¼ of the firstspace, that is, the length a in the +X direction and the −X directionfrom the rectangular portion 15 and the width in the +Y direction andthe −Y direction from the rectangular portion 15 is a width ¼ of thefirst space, that is, the length a. That is, the BOX region 16 is formedinto the shape of a square the side of which is three times the length a(3 a). There is a case where the “length a” of the line-cutting part 14is not equal to the “length a”, which is the width of the first pattern11 and the second pattern 12 because of processes etc. Consequently, therectangular portion 15 and the BOX region 16 are regulated using the“length a” in the line-cutting part 14 so that it is easy to create awiring layout.

As shown in FIG. 2B, a bridge part 17 includes a cross-linking portion18 and the two rectangular portions 15. The cross-linking portion 18extends in the X direction. The length in the X direction is set to alength five times the length a (5 a). The width of the cross-linkingportion 18 is set to the length a. The rectangular portion 15 isprovided at the center portion on the side faces facing in the +Ydirection and the −Y direction of the cross-linking portion 18. Aroundthe rectangular portion 15, the BOX region 16 is set. The BOX region 16around the rectangular portion 15 arranged in the +Y direction of thecross-linking portion 18 is set so that the width is the length a in the+X direction, the −X direction, and the +Y direction from the endportion of the rectangular portion 15. The BOX region 16 around therectangular portion 15 arranged in the −Y direction of the cross-linkingportion 18 is set so that the width is the length a in the +X direction,the −X direction, and the −Y direction from the end portion of therectangular portion 15. There is also a case where the “length a” of thebridge part 17 is not equal to the “length a”, which is the width of thefirst pattern 11 and the second pattern 12, because of processes etc.Consequently, the rectangular portion 15, the BOX region 16, and thecross-linking portion 18 are regulated using the “length a” in thebridge part 17 so that it is easy to create a wiring layout.

Next, a method for designing a wiring layout using the base pattern 10,the line-cutting part 14, and the bridge part 17 described above isexplained.

As shown in FIG. 3, the rectangular portion 15 of the line-cutting part14 is arranged on a portion of the first pattern 11 where it is to bedivided, for example, on the first pattern 11 in a region 19. Further,the rectangular portion 15 of the line-cutting part 14 is arranged on aportion of the second pattern 12 where it is to be divided, for example,on the second pattern 12 in a region 20.

Furthermore, the bridge part 17 is arranged between the first patterns11 to be connected, for example, between the two neighboring firstpatterns 11 sandwiching the one second pattern 12 in a region 21. Inthat case, the cross-linking portion 18 is arranged so as to connect theneighboring first patterns 11 (to span the second pattern 12 on whichthe rectangular portion 15 is arranged). The rectangular portion 15 isarranged on the second pattern 12. Because of that, the second pattern12 on which the bridge part 17 is arranged is divided in the Ydirection.

The bridge part 17 is arranged between the second patterns 12 to beconnected, for example, between the two neighboring second patterns 12sandwiching the one first pattern 11 in a region 22. In that case, thecross-linking portion 18 is arranged so as to span the second pattern12. The rectangular portion 15 is arranged on the first pattern 11.Because of that, the second pattern 11 on which the bridge part 17 isarranged is divided in the Y direction.

That is, the bridge part 17 connects the first patterns 11 or the secondpatterns 12 and at the same time, separates the first pattern 11 or thesecond pattern 12 that the bridge part 17 crosses in the Y direction.

When arranging the line-cutting part 14 and the bridge part 17, the “BOXrules” are applied. The “BOX rules” regulate positions where theline-cutting part 14 and the bridge part 17 can be arranged.

The first rule is that the BOX region 16 in the line-cutting part 14must not overlap the BOX region 16 in another line-cutting part 14.

The second rule is that the BOX region 16 in the line-cutting part 14must not overlap the BOX region 16 in the bridge part 17.

The third rule is that the contact between the BOX regions 16 ispermitted. This means that, for example, the BOX regions 16 in theregion 20 and in the region 22 may be in contact with each other.

The fourth rule is that the BOX regions 16 of the bridge parts 17 mayoverlap each other unless the rectangular portion 15 overlaps therectangular portion 15 of another bridge part 17. This means that theBOX regions 16 of the bridge parts 17 in the region 22 and in the region23 may overlap each other.

Next, as shown in FIG. 4, after arranging the line-cutting parts 14 andthe bridge parts 17 in positions on the base pattern 10 according to theBOX rules, the first patterns 11 and the second patterns 12 on which theline-cutting parts 14 and the bridge parts 17 are arranged are replacedwith patterns. This replacement is performed automatically by a computerin which a layout tool is installed. For example, the replacement isperformed by a designer pressing a conversion button after arranging afixed number of the line-cutting parts 14 and the bridge parts 17.

The designer can not only arrange the parts, but also layout accordingto a rule. For example, the designer can connect two of the firstpatterns 11, or separate the second pattern 12 which is disposed betweenthe first patterns 11.

For example, the portions (the region 19 and the region 20) where theline-cutting part 14 is arranged in the first pattern 11 and the secondpattern 12 are replaced with layout patterns. Here, the replacement isvisual replacement by a computer by which respective parts are replacedvisually with the first and second patterns. Due to this replacement,the first pattern 11 in the region 19 and the second pattern 12 in theregion 20 are turned into two patterns, respectively, in which thepatterns are separated in the Y direction and between the patterns nobridge part is arranged. In FIG. 4 also, the XY rectangular coordinatesystem adopted in FIG. 1 for explaining the base pattern 10 is adopted.

On the other hand, the portion (the region 21) where the bridge part 17is arranged in the first patterns 11 is replaced with a layout pattern.Due to this, the region 21 is replaced with the first pattern 11extending in the X direction and connecting the two first patterns 11and at the same time, the one second pattern 12 intersecting the bridgepart 17 is separated into the two second patterns 12 sandwiching thebridge part 17 and not contacting the bridge part 17. Similarly, in theregion 22, the second pattern 12 on which the bridge part 17 is arrangedis replaced with the second pattern 12 extending in the X direction andconnecting the two second patterns 12 and at the same time, the onefirst pattern 11 intersecting the bridge part 17 is separated into thetwo second patterns 12 sandwiching the bridge part 17 and not contactingthe bridge part 17.

As a result of such replacement, the first patterns 11 and the bridgepart 17 connecting the first patterns 11, and the second patterns 12 andthe bridge part 17 connecting the second patterns 12 are turned intopatterns separated from each other.

After that, the layout pattern in FIG. 4 is converted into actual maskdata. This conversion is performed automatically by a computer etc. inwhich a conversion tool is installed. For example, when the computerexecutes conversion so that the first pattern 11 corresponds to amandrel, the computer converts the layout pattern into mask data bywhich the portion where the first pattern 11 is arranged forms a mandreland the second pattern 12 is deleted.

Explanation is given below using a layout pattern for forming a mandrelin the portion of the first pattern 11 as an example. The computerconverts the portion (the region 19) where the line-cutting part 14 isarranged in the first pattern 11 into mask data by which a mandrelpattern shown in FIG. 8A is formed. Similarly, the computer replaces theportion (the region 20) where the line-cutting part 14 is arranged inthe second pattern 12 with mask data by which a mandrel pattern shown inFIG. 9A is formed.

Due to this, in the final wiring shape, the patterns in the region 19and the region 20 are turned into two patterns separated from each otherin the Y direction and between which no pattern is arranged.

On the other hand, the computer replaces the portion (the region 21) inwhich the bridge part 17 is arranged in the first patterns 11 with maskdata by which a mandrel pattern shown in FIG. 6A is formed. Due to this,in the final wiring shape, the region 21 is turned into the patternextending in the X direction and connecting the two patterns and at thesame time, the pattern extending in the Y direction is separated intotwo patterns so as to sandwich the bridge part 17. Similarly, in theregion 22, the computer converts the portion (the region 22) where thebridge part 17 is arranged in the second patterns 12 into mask data bywhich a mandrel pattern shown in FIG. 7A is formed. In the final wiringshape, the region 22 is turned into the pattern extending in the Xdirection and connecting the two second patterns 12 and at the sametime, the pattern extending in the Y direction is separated into twopatterns sandwiching the bridge part 17.

As will be described later, it is possible to form the wiring layoutdesigned in this manner by the sidewall method. That is, according tothe method for designing a wiring layout according to the embodiment, itis possible to easily design a wiring layout that can be formed by thesidewall method.

According to the design method of a wiring layout according to theembodiment, it is possible to design a wiring layout including anH-shaped connection pattern in which two patterns extending in onedirection are connected by the bridge part 17.

Further, it is possible to design a wiring layout including a pattern inwhich the pattern is separated in the direction in which the patternextends in both the first pattern 11 and the second pattern 12.Hereinafter, this is simply referred to as a “separated pattern” in somecases.

Furthermore, the first patterns 11 and the bridge part 17 connecting thefirst patterns 11, and the second patterns 12 and the bridge part 17connecting the second patterns 12 are turned into patterns separatedfrom each other, and therefore, it is possible to turn one of the firstpatterns 11 and the bridge part 17 connecting the first patterns 11 andthe second patterns 12 and the bridge part 17 connecting the secondpatterns 12 into a pattern of a mandrel of a wiring layout formed by thesidewall method. Consequently, it is possible to design a wiring layoutincluding an H-shaped pattern and a separated pattern in a wiring layoutformed by the sidewall method easily. Therefore, it is possible to aimat high integration of a wiring layout.

Next, a program for supporting a design of a wiring layout formed by thesidewall method is explained.

The program according to the embodiment causes a computer to execute theprocedures shown below.

The program causes the computer to execute a procedure to display thebase pattern 10 on a display unit, for example, a display. As shown inFIG. 1, on the base pattern 10, a plurality of the first patterns 11extending in the Y direction and arranged at the first space in the Xdirection and a plurality of the second patterns 12 extending in the Ydirection and arranged at the center between the first patterns 11 areprovided. It is preferable for the computer to classify the firstpattern 11 and the second pattern 12 by different colors or hatch themdifferently so that it is easy for a designer to make a layout.

Further, the program also causes the computer to execute a procedure todisplay the line-cutting part 14 and the bridge part 17.

The designer, via an input unit, arranges the bridge part 17 in aposition between the two neighboring first patterns 11 sandwiching theone second pattern 12 in the base pattern 10 displayed on the displayunit by, for example, the drag operation of a mouse. At this time, theprogram causes the computer to execute a procedure to connect the twofirst patterns 11 and at the same time, to replace the one secondpattern 12 with two patterns sandwiching the bridge part 17 and notcontacting the bridge part 17.

The designer, via the input unit, arranges the bridge part 17 in aposition between the two neighboring second patterns 12 sandwiching theone first pattern 11 in the base pattern 10 displayed on the displayunit. At this time, the program causes the computer to execute aprocedure to connect the two second patterns 12 and at the same time, toreplace the one first pattern 11 with two patterns sandwiching thebridge part 17 and not contacting the bridge part 17.

The designer, via the input unit, arranges the line-cutting part 14 in aposition on the first pattern 11 in the base pattern 10 displayed on thedisplay unit. At this time, the program causes the computer to execute aprocedure to replace the first pattern 11 with two patterns which areseparated from each other in the Y direction and between which no bridgepart 17 is arranged.

The designer arranges the line-cutting part 14 in a position on thesecond pattern 12 in the base pattern 10 displayed on the display unitvia the input unit. At this time, the program causes the computer toexecute a procedure to replace the second pattern 12 with two patternswhich are separated from each other in the Y direction and between whichno bridge part 17 is arranged.

As a result of this, the first patterns 11 and the bridge part 17connecting the first patterns 11, and the second patterns 12 and thebridge part 17 connecting the second patterns 12 are turned intopatterns separated from each other.

In this manner, it is possible for the program for supporting a designof a wiring layout formed by the sidewall method to cause the computerto support the design of the wiring layout as shown in FIG. 4.

According to the program according to the embodiment, it is possible tocause a computer to support a design of a wiring layout, and therefore,it is possible to reduce the time which the designer designs a wiringlayout that can be formed by the sidewall method.

It may also be possible for the program to cause a computer to execute aprocedure to replace patterns at a time when a designer clicks aconversion button displayed on the display unit after arranging aplurality of the line-cutting parts 14 and the bridge parts 17 (FIG.49). As a result of that, it is possible for the designer to arrange theline-cutting part 14 and the bridge part 17 in a state where the BOXregion 16 is displayed, and therefore, it is possible for the designerto make a layout while confirming the BOX rules (FIG. 49).

Next, a method for manufacturing a pattern by the sidewall method isexplained. As an example, explanation is given using the damascenemethod in which a pattern is embedded in a groove.

FIGS. 5A to 5C are process plan views illustrating a method formanufacturing a pattern by the sidewall method according to the firstembodiment and FIGS. 5D to 5F are process section views along A-A′ planeshown in FIGS. 5A to 5C, respectively.

FIGS. 6A to 6C are process plan views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern connecting between neighboring sidewalls.

FIGS. 7A to 7C are process section views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern connecting neighboring mandrels.

FIGS. 8A to 8C are process plan views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern between separated sidewalls.

FIGS. 9A to 9C are process plan views illustrating the method formanufacturing a pattern by the sidewall method according to the firstembodiment, showing a method for manufacturing a pattern correspondingto a pattern of a separated mandrel.

FIGS. 10 to 13 are plan views illustrating a method for manufacturing asemiconductor device according to the first embodiment.

As shown in FIGS. 5A and 5D, an insulating film 32 is formed on asemiconductor substrate 31. Then, on the insulating film 32, a materialfilm that forms a mandrel 36 is formed. Further, on the material filmthat forms the mandrel 36, a resist film (not shown schematically) isformed. Next, the resist film is subjected to patterning by thelithography method. Patterning is performed by irradiating a mask (notshown schematically) placed on the resist film with exposure light. Atthis time, the width of a pattern formed on the resist film is theminimum processing dimension value of lithography in many cases.

The material film that forms the mandrel 36 is etched using thepatterned resist film as a mask. Due to this, the mandrel 36 is formed.The mandrel 36 is thinned by slimming according to the necessity. Here,the width of the final mandrel 36 is substantially equal to the “lengtha” in the wiring layout.

A sidewall 37 is formed on the side face of the mandrel 36. The sidewall37 is formed by, for example, removing a flat portion of a material filmthat forms the sidewall 37 by performing anisotropic etching afterforming the material film that forms the sidewall 37 on thesemiconductor substrate 31 so as to cover the mandrel 36 and thenleaving the portion on the side face of the mandrel 36. As a result ofthat, the sidewall 37 is formed into the shape of a closed loop thatsurrounds the mandrel 36 when viewed in the top view. It is preferablefor the thickness of the material film that forms the sidewall 37 to bethe same as the width of the mandrel 36. Further, the thickness of thematerial film that forms the sidewall 37 is reduced smaller than alength ½ of the space between the neighboring mandrels 36. Due to this,a gap is formed between the sidewalls 37 of the neighboring mandrels 36.Hereinafter, this gap is referred to as an “inter-mandrel gap 38”. As aresult of that, the length of the inter-mandrel gap 38 is substantiallythe same as the width between the first pattern 11 and the secondpattern 12 in the wiring layout.

As shown in FIGS. 5B and 5E, the mandrel 36 is removed. Then, by etchingthe insulating film 32 using the sidewall 37 as a mask, the insulatingfilm 32 is removed selectively and thus a concave portion 39 is formed.According to the necessity, the end portion of the sidewall 37 in theshape of a closed loop is removed. This process is sometimes referred toas a “loop-cut process”.

As shown in FIGS. 5C and 5F, the sidewall 37 is removed. After that, anelectrically conductive material is deposited on the insulating film 32so as to fill in the concave portion 39. Then, the electricallyconductive material is flattened until the top face of the insulatingfilm 32 is exposed. In this manner, a pattern 40 embedded in the concaveportion 39 is formed.

The length of the space between the patterns 40 neighboring in adirection perpendicular to the direction in which the pattern 40embedded in the concave portion 39 and including the electricallyconductive material extends is smaller than the length of the minimumspace of patterns that can be separated by the lithography method usedwhen patterning a resist film 34.

Next, a method for forming the pattern 40 corresponding to an H-shapedpattern by the sidewall method is explained.

A case where the pattern 40 formed within the concave portion 39 of theinter-mandrel gap 38 is connected in the sidewall method is explained.

As shown in FIG. 6A, as a pattern of the mandrel 36, patterns of the twomandrels 36 separated on the way are formed between the two patternsextending in the Y direction. The patterns of the two mandrels 36separated on the way are formed by the lithography method using a maskin the same shape as the shape of the mandrel 36. The mandrel 36 isslimmed so that the width of the mandrel is W. Further, in the patternsof the mandrels 36 separated on the way, a space L1 in the Y directionis set to a space substantially not less than a space D in the Xdirection between the mandrels 36.

As shown in FIG. 6B, the sidewall 37 is formed on the side face of themandrel 36. The thickness of the sidewall 37 on the side face of themandrel 36 is reduced smaller than L1/2. Due to this, even if thesidewall 37 is formed at the end portion of the separated mandrel 36, itis unlikely that the portion separated by the sidewall 37 is closed.Further, the inter-mandrel gap 38 extending in the X direction at theseparated portion is connected with the inter-mandrel gap 38 formedbetween the separated mandrel 36 and the mandrel 36 adjacent thereto andextending in the Y direction. Due to this, shape of the inter-mandrelgap 38 is formed into the shape of H.

As shown in FIG. 6C, the mandrel 36 is removed. Due to this, in theportion from which the separated mandrel 36 is removed, a pattern of theseparated patterns 40 is formed.

By performing processes shown in FIGS. 5B and 5E, and FIGS. 5C and 5F,it is possible to form the pattern 40 corresponding to the H-shapedpattern.

Next, another method for forming the pattern 40 corresponding to theH-shaped connection pattern is explained.

As shown in FIG. 7A, as a pattern of the mandrel 36, an H-shaped patternis formed. The pattern of the H-shaped mandrel 36 is formed by thelithography method described previously. As an example, a case isexplained where the width of the H-shaped mandrel 36 is W and the widthof the connection portion of the pattern of the H-shaped mandrel 36 isalso W. The width of the connection portion of the H-shaped mandrel 36can be formed by the lithography method and any width is acceptableunless it disappears by slimming.

As shown in FIG. 7B, the sidewall 37 is formed on the side face of themandrel 36. In the +Y and −Y directions of the mandrel 36 extending inthe X direction, a pattern of the separated inter-mandrel gap 38 isformed.

As shown in FIG. 7C, the mandrel 36 is removed. Due to this, an H-shapedpattern is formed at the portion from which the mandrel 36 is removed.

After that, by performing the processes shown in FIGS. 5B and 5E, and 5Cand 5F, it is possible to form the pattern 40 corresponding to theH-shaped pattern.

Next, a method for forming a pattern corresponding to a separatedpattern by the sidewall method is explained.

As shown in FIG. 8A, as a pattern of the mandrel 36, the mandrel 36extending in the Y direction is formed. When the pattern of theinter-mandrel gap 38 is formed into two separated patterns, in thepattern of the mandrel 36 sandwiching the region between the twoseparated patterns, a convex portion 42 protruding toward the regionbetween the two patterns is formed. A space L2 between the convexportions 42 in the mandrels 36 is set to a space not more than twice thethickness of the sidewall 37 on the side face of the mandrel 36. Thespace L2 is, for example, a width thinned by slimming after formed bythe lithography method when slimming is used.

As shown in FIG. 8B, the sidewall 37 is formed on the side face of themandrel 36. Due to this, the sidewalls 37 formed on the side faces ofthe convex portions 42 couple with each other at the portion between theconvex portions 42 and the inter-mandrel gap 38 at the portion isseparated in the Y direction.

As shown in FIG. 8C, the mandrel 36 is removed. By performing theprocesses in FIGS. 5B and 5E, and 5C and 5F, the pattern is formed. Dueto this, it is possible to form the pattern 40 corresponding to thepattern of the separated inter-mandrel gap 38. In the two patternssandwiching the region between the separated two patterns 40, a convexpart 44 protruding toward the region between the two patterns is formed.

Further, as shown in FIG. 9A, when the pattern of the mandrel 36 isseparated into two patterns, as a pattern of the mandrel 36, the mandrel36 extending in the Y direction is formed. Then, a portion 36 a locatedbetween the two separated patterns is made thinner than other portions.It is preferable for the length L2 in the Y direction of the portion 36a to be shorter than the width W of the mandrel 36. After formed by thelithography method, the portion 36 a may disappear by slimming. In theexample, a case where the portion 36 a disappears by slimming isexplained.

As shown in FIG. 9B, the sidewall 37 is formed on the side face of themandrel 36. Due to this, the sidewalls 37 formed on the side faces onboth sides of the thinned mandrel 36 become not more than twice the filmthickness of the material of the sidewall 37 at the portion 36 a, andtherefore, the sidewalls coupled with each other at the portion 36 a.When the portion 36 a of the mandrel 36 thinned by slimming remains, theportion 36 a is not removed but remains by the subsequent etching of themandrel 36 because the portion 36 a is thin. Due to this, it is possibleto form the pattern of the mandrel 36 into two separated patterns. Onthe other hand, in the inter-mandrel gap 38 sandwiching the portion ofthe thinned mandrel 36, a concave portion 43 is formed.

As shown in FIG. 9C, the mandrel 36 is removed. By performing theprocesses in FIGS. 5B and 5E, and 5C and 5F, it is possible to form thepattern 40 corresponding to the pattern of the separated mandrel 36.Further, in the two patterns sandwiching the region between the twoseparated patterns, the convex portion 44 protruding toward the regionbetween the two patterns is formed.

Next, a method for manufacturing a semiconductor device based on awiring layout including the line-cutting part 14 and the bridge part 17described previously is explained.

As shown in FIG. 10, in the wiring layout described previously, themandrel 36 is formed on the insulating film 32 using one of the firstpatterns 11 and the bridge part 17 connecting the first patterns 11, andthe second patterns 12 and the bridge part 17 connecting the secondpatterns 12 as a pattern of the mandrel 36. After that, slimming isperformed according to the necessity.

For example, the mandrel 36 is formed on the insulating film 32 usingthe second patterns 12 and the bridge part 17 connecting the secondpatterns 12 in FIG. 4 in the embodiment as the pattern of the mandrel36.

At the portion (the region 20) that forms the pattern of the separatedmandrel 36, the portion 36 a located between the two patterns to beseparated is made thinner than other portions. At the portion (theregion 19) that forms the pattern of the separated inter-mandrel gap 38,in the pattern of the two mandrels 36 sandwiching the region between theseparated two patterns, the convex portion 42 protruding toward theregion is formed.

As shown in FIG. 11, on the side face of the mandrel 36, the sidewall 37is formed. In the region 20, the formed sidewall 37 is caused toeliminate the thin portion 36 a by slimming or the mandrel 36 sandwichedby the sidewalls 37 is prevented from being removed by the subsequentetching of the mandrel 36. When the portion 36 a is eliminated byslimming, the length of the portion 36 a is set to a length not morethan twice the film thickness of the material of the sidewall 37. In theregion 19, the sidewalls 37 formed on the side faces of the convexportions 42 connect with each other and an inter-mandrel gap 38 isseparated.

As shown in FIG. 12, the mandrel 36 is removed by etching.

After that, the processes in FIGS. 5B and 5E, and 5C and 5F areperformed.

As shown in FIG. 13, a semiconductor device 1 including the pattern 40formed based on the wiring layout shown in FIG. 4 is manufactured.

According to the method for manufacturing a semiconductor deviceaccording to the embodiment, it is possible to manufacture thesemiconductor device 1 including the pattern 40 of the H-shaped patternand the separated pattern 40.

Further, it is possible to form the H-shaped pattern 40 and theseparated pattern 40 by using one of the pattern of the mandrel 36 andthe pattern of the inter-mandrel gap 38 with the convex portion 42.Consequently, it is made possible to create a free design including awiring space narrower than the minimum value of space by the resolutionof lithography, and therefore, it is possible to manufacture asemiconductor device including highly integrated patterns.

Next, the semiconductor device 1 according to the first embodiment isexplained.

As shown in FIGS. 5A to 5F and FIG. 13, the semiconductor device 1includes the semiconductor substrate 31 and the pattern 40 provided onthe semiconductor substrate 31.

In the semiconductor device 1, a plurality of patterns 51 correspondingto a plurality of the first patterns 11 extending in the Y direction, aplurality of patterns 52 corresponding to a plurality of the secondpatterns 12 extending in the Y direction, a plurality of patterns 53corresponding to a plurality of the bridge parts 17 extending in the Xdirection and connecting the first patterns 11, and a plurality ofpatterns 54 corresponding to a plurality of the bridge parts 17extending in the X direction and connecting the second patterns 12 areprovided.

If a plurality of lines extending in the Y direction and arranged at aspace ½ of the first space in the X direction are supposed in the XYplane and integers are allocated from one to the lines in order from theend, the patterns 51 are arranged in the odd-numbered lines and thepatterns 52 in the even-numbered lines.

Further, the pattern 53 connects the patterns 51 and the pattern 54connects the patterns 52. Then, the pattern 51 and the pattern 53, andthe pattern 52 and the pattern 54 are separated from each other.

In the region 19, two of the patterns 51 are arranged in the same lineextending in the Y direction, separated from each other in the Ydirection, and the pattern 54 is not arranged therebetween.

In the region 20, two of the patterns 52 are arranged in the same lineextending in the Y direction, separated from each other in the Ydirection, and the pattern 53 is not arranged therebetween.

Then, in the two patterns 52 sandwiching a region 55 between the twopatterns 51 in the X direction, the convex portion 42 protruding towardthe region 55 is formed.

Further, in the two patterns 51 sandwiching a region 56 between the twopatterns 52 in the X direction, the convex portion 42 protruding towardthe region 56 is formed.

According to the method for manufacturing a semiconductor deviceaccording to the embodiment, it is possible to manufacture ahighly-integrated semiconductor device including the H-shaped pattern 40and the separated pattern 40 and a wiring space narrower than theminimum value of space by the resolution of lithography.

Second Embodiment

Next, a second embodiment is explained.

First, a method for designing a wiring layout formed by the sidewallmethod according to the second embodiment is explained.

FIG. 14 is a plan view illustrating a base pattern to be used in themethod for designing a wiring layout according to the second embodiment.

FIGS. 15A to 15D are plan views illustrating layout parts used in thesecond embodiment, wherein FIG. 15A illustrates a line-cutting part,FIG. 15B a Y bridge part, FIG. 15C an X bridge part, and FIG. 15D acontact fringe.

FIG. 16 is a plan view illustrating a state where the bridge parts arearranged on the base pattern in the second embodiment.

As shown in FIG. 14, on a base pattern 60 according to the embodiment, aplurality of first points 61 arranged in a matrix and a plurality ofsecond points 62 arranged in a matrix are provided.

The plurality of the first points 61 are arranged in a matrix at thesecond space in the Y direction and at the first space in the Xdirection. The plurality of the second points 62 are arranged in amatrix at the second space in the Y direction and at the first space inthe X direction. However, the second points 62 are arranged at a spaceshifted by half the second space in the Y direction and arranged at aspace shifted by half the first space in the X direction with respect tothe first points.

In the embodiment, the first space and the second space are made thesame. Further, the first point 61 and the second point 62 are formedinto the shape of a square and the length of one side is set to thelength a ¼ of the first and second spaces.

As shown in FIG. 15A, a line-cutting part 64 includes a rectangularportion 65. The rectangular portion 65 is formed into the shape of asquare. The length of one side is set to the length a.

As shown in FIG. 15B, a Y bridge part 66 includes a Y cross-linkingportion 67 and the two rectangular portions 65. The Y cross-linkingportion 67 extends in the Y direction. The length in the Y direction isset to a length five times the length a (5 a). The width of the Ycross-linking portion 67 is set to the length a, the same as the lengthof one side of the rectangular portion 65. The rectangular portion 65 isprovided at the center on the side face in the X direction of the Ycross-linking portion 67.

As shown in FIG. 15C, an X bridge part 68 includes an X cross-linkingportion 69 and the two rectangular portions 65. The X cross-linkingportion 69 extends in the X direction. The length in the X direction isset to a length five times the length a. The width of the Xcross-linking portion 69 is set to the length a, the same as the lengthof one side of the rectangular portion 65. The rectangular portion 65 isprovided at the center on the side face in the Y direction of the Xcross-linking portion 69.

As shown in FIG. 15D, a contact fringe 70 includes a contact portion 71and the four rectangular portions 65. The contact portion 71 is formedinto the shape of a rectangle and the length of the side in the Ydirection is set to a length five times the length a (5 a), the same asthe length of the Y cross-linking portion 67, and the length of the sidein the X direction is set to a length five times the length a (5 a), thesame as the length of the X cross-linking portion 69. The fourrectangular portions 65 are provided at the centers on the side faces ofthe four sides of the contact portion 71. That is, one pair of therectangular portions 65 is on the same line in the X direction and theother pair is on the same line in the Y direction.

As shown in FIG. 16, the Y bridge part 66 is arranged between the firstpoints 61 adjacent to each other in the Y direction and between thesecond points 62 adjacent to each other in the Y direction. Next, the Xbridge part 68 is arranged between the first points 61 adjacent to eachother in the X direction and between the second points 62 adjacent toeach other in the X direction. That is, the X bridge part 68 and the Ybridge part 66 are arranged so that the end portions of the Xcross-linking portion 69 and the Y cross-linking portion 67 overlap thefirst points 61 or the second points 62.

Further, the contact fringe 70 is arranged so that the four corners ofthe contact portion 71 overlap the four first points 61 arranged so asto surround the second point 62 with one of the second points 62 as areference. It is also possible to arrange the contact fringe 70 so thatthe four corners of the contact portion 71 overlap the four secondpoints 62 arranged so as to surround the first point 61 with one of thefirst points 61 as a reference.

If necessary, the line-cutting part 64 is arranged at the portion to beseparated in the Y cross-linking portion 67 and the X cross-linkingportion 69.

In this manner, a wiring layout formed by the sidewall method ismanufactured.

According to the method for designing a wiring layout according to theembodiment, a pattern including a plurality of points arranged in theform of a two-dimensional matrix is used as the base pattern 60, andtherefore, it is made possible to create a freer design not limited to apattern extending in one direction while aiming at higher integration ofthe wiring layout.

Further, according to the embodiment, the X bridge part 68 and the Ybridge part 66 connecting the first points 61 and the X bridge part 68and the Y bridge part 66 connecting the second points 62 are turned intopatterns separated from each other. Consequently, it is possible to makea wiring layout formed by the sidewall method.

Next, a base pattern according to a modified example of the secondembodiment is explained.

FIG. 17 is a plan view illustrating a base pattern according to amodified example of the second embodiment.

As shown in FIG. 17, on a base pattern 72, a lattice pattern in whichthe second points 62 are connected by the X bridge parts 68 and the Ybridge parts 66 and the first point 61 arranged at the center of eachlattice are provided.

The line-cutting part 64, the X bridge part 68, the Y bridge part 66,and the contact fringe 70 are arranged in predetermined positions in thebase pattern 72. Due to this, a wiring layout is manufactured.

According to the modified example, it is sufficient to arrange the Xbridge part 68 and the Y bridge part 66 so as to connect the firstpoints 61 and it is not necessary to arrange the X bridge part 68 andthe Y bridge part 66 on the second point 62. Consequently, it ispossible to eliminate the process of arranging the bridge parts. It ispossible to arrange the contact fringe 70 so that the center portion ofthe contact portion 71 overlaps one of the first point 61 and the secondpoint 62. In the case of FIG. 17, when the center portion of the contactportion 71 of the contact fringe 70 is overlapped on the second point62, the X bridge part 68 and the Y bridge part 66 connected to thesecond point 62 are separated by the rectangular portion 65 of thecontact fringe 70.

Next, a program for supporting a design of a wiring layout formed by thesidewall method is explained.

The program according to the embodiment causes a computer to executeprocedures shown below.

The program causes the computer to execute a procedure to display thebase pattern 60 on the display unit. On the base pattern 60, a pluralityof the first points 61 arranged in a matrix at the second space in the Ydirection and at the first space in the X direction and a plurality ofthe second points 62 arranged in a matrix at the second space in the Ydirection and at the first space in the X direction, the second points62 being arranged at a space shifted by half the second space in the Ydirection and arranged at a space shifted by half the first space in theX direction with respect to the first point, are provided.

The program causes the computer to execute a procedure to display theline-cutting part 64, the X bridge part 68, the Y bridge part 66, andthe contact fringe 70 on the display unit. It is preferable for thecomputer to classify the first points 61 and the second points 62, orthe lattice pattern connecting the second points by different colors orhatch differently to make it easy for a designer to make a layout.

When the designer, via the input unit, arranges the Y bridge part 66 ina predetermined position between the two first points 61 adjacent toeach other in the Y direction in the base pattern 60 displayed on thedisplay unit by, for example, the drag operation of a mouse, the programcauses the computer to execute a procedure to connect the two firstpoints 61.

When the designer, via the input unit, arranges the X bridge part 68 ina predetermined position between the two first points 61 adjacent toeach other in the X direction in the base pattern 60 displayed on thedisplay unit, the program causes the computer to execute a procedure toconnect the two first points 61.

Similarly, the program also causes the computer to execute a procedureto connect the two second points 62 by the X bridge part 68 and the Ybridge part 66. That is, when the Y bridge part 66 is arranged in aposition between the two second points 62 adjacent to each other in theY direction in the base pattern 60 displayed on the display unit, theprogram causes the computer to execute a procedure to connect the twosecond points 62 and when the X bridge part 68 is arranged in a positionbetween the two second points 62 adjacent to each other in the Xdirection in the base pattern 60 displayed on the display unit, theprogram causes the computer to execute a procedure to connect the twosecond points 62

When the designer arranges, via the input unit, the contact fringe 70 onthe following four first points 61 displayed on the display unit, thatis, on the one first point 61, on the first point 61 adjacent thereto inthe X direction with the one first point 61 as a reference, and on thetwo first points 61 adjacent to the two first points 61 in the Ydirection, the program causes the computer to execute a procedure toarrange the contact fringe on the four first points 61.

When the designer arranges, via the input unit, the line-cutting part 64on the portions to be separated in the Y cross-linking portion 67 andthe X cross-linking portion 69, the program causes the computer toexecute a procedure to replace the portions with two separated patterns.

In this manner, a wiring layout formed by the sidewall method ismanufactured.

According to the program according to the embodiment, it is possible tocause a computer to support a design of a wiring layout, and therefore,it is possible to reduce the time which the designer designs a wiringlayout that can be formed by the sidewall method.

It may also be possible for the program to cause the computer to executea procedure to replace patterns at a time when the designer clicks aconversion button displayed on the display unit after arranging aplurality of the X bridge parts 68 etc (FIG. 49). As a result of that,it is possible for the designer to arrange other parts in a state whereeach part is displayed, and therefore, making a layout is made easy.

Next, a method for manufacturing a semiconductor device includingpatterns formed based on a wiring layout by the sidewall method isexplained.

FIGS. 18A to 18D are plan views illustrating a method for manufacturinga semiconductor device according to the second embodiment.

As shown in FIG. 18A, in the wiring layout described previously, themandrel 36 is formed on the insulating film 32 using one of the Y bridgepart 66 and the X bridge part 68 connecting the first points 61 and theY bridge part 66 and the X bridge part 68 connecting the second points62 as a pattern of the mandrel 36.

For example, in FIG. 16 in the embodiment, the mandrel 36 is formed onthe insulating film 32 using the Y bridge part 66 and the X bridge partconnecting the first points 61 as a pattern of the mandrel 36. Accordingto the necessity, the mandrel 36 is slimmed.

As shown in FIG. 18B, the sidewall 37 is formed on the side face of themandrel 36. The relationship between the width of the mandrel 36 and thefilm thickness of the sidewall 37 is the same as the relationship in thefirst embodiment.

As shown in FIG. 18C, the mandrel 36 is removed by etching.

The processes in FIGS. 5B and 5E, and 5C and 5F are performed.

In this manner, as shown in FIG. 18D, a semiconductor device 2 includingpatterns formed based on the above-described wiring layout ismanufactured.

According to the method for manufacturing a semiconductor deviceaccording to the embodiment, it is possible to form the H-shaped pattern40 and the separated pattern 40 using one of the patterns of the mandrel36 and the inter-mandrel gap 38. Consequently, it is made possible todesign a wiring layout including a wiring space narrower than theminimum value of space by the resolution of lithography easily. Andtherefore, it is possible to manufacture a semiconductor deviceincluding highly integrated patterns. In particular, it is possible todesign patterns mainly based on the final layout instead of designingpatterns by calculating the sidewall 37 from the mandrel 36. As a resultof that, the design efficiency is improved considerably.

Next, the semiconductor device 2 according to the embodiment isexplained.

In the semiconductor device 2, a plurality of patterns 82 correspondingto the Y bridge part 66 connecting the first points 61, a plurality ofpatterns 82 corresponding to the Y bridge part 66 connecting the secondpoints 62, a plurality of patterns 83 corresponding to the X bridge part68 connecting the first points 61, and a plurality of patterns 84corresponding to the X bridge part connecting the second points 62 areprovided.

If a plurality of first lines extending in the Y direction and arrangedat a space ½ of the first space in the X direction are supposed in theXY plane and integers are allocated from one to the first lines in orderfrom the end, and if a plurality of second lines extending in the Xdirection, arranged at a space ½ of the second space in the Y direction,and intersecting the first lines are supposed in the XY plane andintegers are allocated from one to the second lines in order from theend, the patterns are arranged in the odd-numbered first lines and thepatterns 82 are arranged in the even-numbered first lines. Further, thepatterns 83 are arranged in the odd-numbered second lines and thepatterns 84 are arranged in the even-numbered second lines.

Then, at least one of the patterns 81 connects with the pattern 83 andat least one of the patterns 82 connects with the pattern 84. Further,the pattern 81 and the pattern 83, and the pattern 82 and the pattern 84are separated from each other.

The semiconductor device 2 according to the embodiment includes theH-shaped pattern and the separated pattern and also includes the wiringspace narrower than the minimum value of space by the resolution oflithography, and therefore, the degree of integration is high.

Third Embodiment

Next, a third embodiment is explained.

The embodiment is an embodiment of a method for designing a wiringlayout formed by the two-time sidewall method.

First, a method for designing a wiring layout according to theembodiment is explained.

FIG. 19 is a plan view illustrating a base pattern used in the methodfor designing a wiring layout according to the third embodiment.

FIGS. 20A to 20D are plan views illustrating layout parts used in thethird embodiment, wherein FIG. 20A shows a line-cutting part and FIGS.20B to 20D show bridge parts.

FIG. 21 is a plan view illustrating a state where the bridge parts andline-cutting parts are arranged on the base pattern.

FIG. 22 is a plan view illustrating a state where patterns and thebridge parts are classified by three colors in the third embodiment.

First, the base pattern and each part used in the embodiment areexplained.

As shown in FIG. 19, on a base pattern 90 used in the embodiment, aplurality of first patterns 91 extending in one direction, a pluralityof second patterns 92 extending in the one direction, and a plurality ofthird patterns 93 extending in the one direction are provided.

In the embodiment also, in order to explain the base pattern 90, thesame XY rectangular coordinate system as in the first embodimentdescribed previously is adopted. In the XY rectangular coordinatesystem, of the directions in which the first pattern 91, the secondpattern 92, and the third pattern 93 extend, the upward direction in thefigure is referred to as the +Y direction and the opposite direction isreferred to as the −Y direction. The “+Y direction” and the “−Ydirection” are together referred to also as the “Y direction”. Thedirection 90 degrees rotated clockwise from the +Y direction is referredto as the +X direction and the opposite direction is referred to as the−X direction. The “+X direction” and the “−X direction” are togetherreferred to also as the “X direction”.

The first patterns 91 extend in the Y direction and are arranged at thefirst space along the X direction. The end in the +Y direction of thefirst pattern 91 is referred to as an end 91 a and the end in the −Ydirection of the first pattern 91 is referred to as an end 91 b.

The second patterns 92 extend in the Y direction and are arranged one byone at the center between the first patterns 91. Consequently, thesecond patterns 92 are arranged at the first space in the X direction.The end in the +Y direction of the second pattern 92 is connected to ahorizontal pattern 94 extending in the horizontal direction. The end inthe −Y direction of the second pattern 92 is connected to a horizontalpattern 95 extending in the X direction.

The third patterns 93 extend in the Y direction and are arranged one byone at the center between the first pattern 91 and the second pattern 92adjacent to each other. Consequently, the third patterns 93 are arrangedat a space ½ of the first space in the X direction. Further, ends 93 ain the +Y direction of the two third patterns 93 adjacent to each otherwith the one first pattern 91 sandwiched in between are connected by ahorizontal pattern 96 provided between the end 91 a and the horizontalpattern 94 and extending in the X direction. Ends 93 b in the −Ydirection of the two third patterns adjacent to each other with the onefirst pattern 91 sandwiched in between are connected by a horizontalpattern 97 provided between the end 91 b and the horizontal pattern 95and extending in the X direction. That is, the third patterns 93 arearranged so as to surround the one first pattern 91.

In the embodiment, the width of the first pattern 91, the second pattern92, and the third pattern 93 is set to a length ⅛ of the first space.This length is referred to as the length a. The space between the firstpattern 91 and the third pattern 93 and the space between the secondpattern 92 and the third pattern 93 are also the length a.

As shown in FIG. 20A, a line-cutting part 98 includes a rectangularportion 99.

The rectangular portion 99 is formed into the shape of a square eachside of which has the length a, which is the width of the first pattern91 and the second pattern 92.

It is possible to arrange the line-cutting part 98 on the first pattern91 and the second pattern 92 but not on the third pattern 93.

As shown in FIG. 20B, a bridge part 100 includes a cross-linking portion101 and the two rectangular portions 99. The cross-linking portion 101extends in the X direction. The length in the X direction of thecross-linking portion 101 is set to the length a. The width of thecross-linking portion 101 is set to the length a. The rectangularportion 99 is provided at the center portion on the side faces facing inthe +Y direction and the −Y direction of the cross-linking portion 101.

It is possible to arrange the bridge part 100 between the two thirdpatterns 93 sandwiching the one first pattern 91 or the one secondpattern 92.

As shown in FIG. 20C, a bridge part 102 includes the two cross-linkingportions 101 and the five rectangular portions 99. The two cross-linkingportions 101 extend in the X direction and arranged in tandem in the Ydirection. At the center portion and both ends between the twocross-linking portions 101, the three in total rectangular portions 99are arranged. At the center portion on the side face facing in the +Ydirection of the cross-linking portion 101 on the side in the +Ydirection, the rectangular portion 99 is provided. At the center portionon the side face facing in the −Y direction of the cross-linking portion101 on the side in the −Y direction, the rectangular portion 99 isprovided. That is, the rectangular portions 99 are arranged along astraight line in the Y direction at the center portion in the Xdirection of the cross-linking portion 101. Further, the rectangularportions 99 are arranged side by side in the X direction between thecross-linking portions 101.

It is possible to arrange the bridge part 102 between the two thirdpatterns 93 sandwiching the one first pattern 91 or the one secondpattern 92. That is, by overlapping the end portion of the cross-linkingportion 101 on the third pattern 93, the third patterns 93 adjacent toeach other are connected and at the same time, the first pattern 91 orthe second pattern 92 that the cross-linking portion 101 crosses isdivided in the Y direction.

As shown in FIG. 20D, a bridge part 103 includes one large cross-linkingportion 104, the two cross-linking portions 101, and eight rectangularportions. The length of the one large cross-linking portion 104 is setto a length nine times the length a (9 a). The width of the largecross-linking portion 104 is set to the length a. On the side in the +Ydirection and on the side in the −Y direction of the large cross-linkingportion 104, the cross-linking portion 101 is provided. The center inthe X direction of the large cross-linking portion 104 and the center inthe X direction of the cross-linking portion 101 agree in the Xdirection. Between the cross-linking portion 101 on the side in the +Ydirection of the large cross-linking portion 104 and the largecross-linking portion 104, the three in total rectangular portions 99are provided at the center portion and both ends on the side face of thecross-linking portion 101 on the side in the +Y direction. Between thecross-linking portion 101 on the side in the −Y direction of the largecross-linking portion 104 and the large cross-linking portion 104, thethree in total rectangular portions 99 are provided at the centerportion and both ends on the side face of the cross-linking portion 101on the side in the −Y direction. At the center portion on the side facefacing in the +Y direction of the cross-linking portion 101 on the sidein the +Y direction, the rectangular portion 99 is provided. At thecenter portion on the side face facing in the −Y direction of thecross-linking portion 101 on the side in the −Y direction, therectangular portion 99 is provided. That is, the rectangular portions 99are aligned along a straight line in the Y direction at the centerportion in the X direction of the large cross-linking portion 104 andthe cross-linking portion 101. Further, the rectangular portions 99 arealigned along a straight line in the X direction between the largecross-linking portion 104 and the cross-linking portion 101.

It is possible to arrange the bridge part 103 between the two secondpatterns 92 sandwiching the one first pattern 91 and the two thirdpatterns 93 or between the first patterns 91 sandwiching the one secondpattern 92 and the two third patterns 93. That is, by overlapping theend portion of the large cross-linking portion 104 on the first patternand the end portion of the cross-linking portion 101 on the thirdpattern 93, the neighboring first patterns are connected and at the sametime, the second pattern 92 and the third pattern 93 that the largecross-linking portion 104 crosses are divided in the Y direction and thesecond patterns 92 are connected by the cross-linking portion 101 in theX direction.

Next, a method for designing a wiring layout by arranging each partdescribed above on the base pattern 90 is explained.

As shown in FIG. 21, the rectangular portion 99 of the line-cutting part98 is arranged on a portion to be divided in the Y direction in thefirst pattern 91, for example, on the first pattern 91 in a region 105.

When connecting the neighboring third patterns 93 sandwiching the secondpattern 92 in the X direction, the bridge part 100 is arranged betweenthe two third patterns 93 to be connected, for example, between theneighboring two third patterns sandwiching the one second pattern 92 ina region 106. In that case, the cross-linking portion 101 is arranged soas to span the second pattern 92. The rectangular portion 99 is arrangedon the second pattern 92.

Further, when connecting the neighboring third patterns 93 sandwichingthe first pattern 91 in the X direction, the bridge part 102 is arrangedbetween the third patterns 93 to be connected, for example, between thetwo neighboring third patterns 93 sandwiching the one first pattern 91in a region 107. In that case, the two cross-linking portions 101 arearranged so as to span the first pattern 91. The rectangular portion 99is arranged on the first pattern 91 and the second pattern 92.

When connecting the first patterns 91 neighboring in the X direction,the large cross-linking portion 104 in the bridge pattern 103 isarranged between the first patterns 91 to be connected, for example,between the two neighboring first patterns 91 sandwiching the one secondpattern 92 and the two third patterns 92 in a region 108. In this case,the two cross-linking portions 101 are arranged so as to span the secondpattern 92. The rectangular portion 99 is arranged on the second pattern92 and the third pattern 93.

The computer replaces the first pattern 91, the second pattern 92, andthe third pattern 93 in which the line-cutting part 98, the bridge part100, the bridge part 102, and the bridge part 103 are arranged withpredetermined patterns. Here, the replacement is replacement in whichthe computer visually replaces each part with the first and secondpatterns.

As shown in FIG. 22, the computer replaces the first pattern 91 in whichthe line-cutting part 98 is arranged with two patterns separated fromeach other in the Y direction and no bridge part is arranged in between(the region 105)

On the other hand, the computer replaces the third pattern 93 in whichthe bridge part 100 is arranged with a pattern connecting the two thirdpatterns 93 and at the same time, replaces the one second pattern 92intersecting the bridge part 100 with two patterns sandwiching thebridge part 100 and not contacting the bridge part 100 (the region 106).

Further, the computer replaces the two third patterns 93 in which thebridge part 102 is arranged with a pattern connecting the two thirdpatterns separated on the side in the +Y direction and extending in theX direction and a pattern connecting the two third patterns separated onthe side in the −Y direction and extending in the X direction, bothpatterns being separated from each other in the Y direction and at thesame time, replaces the one first pattern 91 intersecting the bridgepart 102 with two patterns sandwiching the bridge part 102 and notcontacting the bridge part 102 (the region 107).

Furthermore, the computer replaces the first pattern 91 in which thebridge part 103 is arranged with one pattern extending in the Xdirection and connecting the two first patterns 91. The computerreplaces the two third patterns 93 intersecting the bridge part 103 withtwo patterns sandwiching the bridge part 103 and not contacting thebridge part 103, respectively. The computer replaces the one secondpattern 91 intersecting the bridge part 103 with two patternssandwiching the bridge part 103 and not contacting the bridge part 103(the region 108).

The computer converts the layout pattern in FIG. 22 into actual maskdata. This conversion is performed automatically by a computer in whicha conversion tool is installed. For example, when a computer convertsthe third pattern 93 so as to correspond to a mandrel, the computerconverts the layout pattern into mask data by which the portion wherethe third pattern 93 is arranged forms a mandrel and converts so thatthe first pattern 91 and the second pattern 92 are deleted.

Hereinafter, explanation is given with an example of a layout pattern inwhich a mandrel is formed on the portion of the third pattern 93. Acomputer converts the portion (the region 105) where the line-cuttingpart 98 is arranged in the first pattern 91 into mask data in which amandrel pattern shown in FIG. 38A is formed. Similarly, the computerconverts the portion (the region 106) where the bridge part 100 isarranged in the third pattern 93 into mask data in which a mandrelpattern shown in FIG. 32A is formed.

The computer replaces the portion (the region 107) where the bridge part102 is arranged in the third pattern 93 with mask data in which amandrel pattern shown in FIG. 24A is formed. The computer replaces theportion (the region 108) where the bridge part 103 is arranged in thefirst pattern 91 with mask data in which a mandrel pattern shown in FIG.28A is formed.

As a result of such replacement, the first patterns 91 and the largecross-linking portion 104 of the bridge part 103 connecting the firstpatterns 91, the second pattern 92, and the third patterns 93 and thebridge parts 100, 102 connecting the third patterns 93 are turned intopatterns separated from one another.

In this manner, it is possible to design a wiring layout formed by thesidewall method.

Next, the effect of the method for designing a wiring layout accordingto the embodiment is explained.

According to the method for designing a wiring layout according to theembodiment, it is possible to design a wiring layout including anH-shaped connection pattern connecting two patterns extending in onedirection by the bridge parts 100, 102, and 103.

Further, it is possible to design a wiring layout including a patternthat forms patterns separated from each other in one direction.

Furthermore, the first patterns 91 and the large cross-linking portion104 of the bridge part 103 connecting the first patterns 91, the secondpattern 92 and the large cross-linking portion 104 of the bridge part103 connecting the second patterns 92, and the third pattern 93 and thecross-linking portions 101 of the bridge part 100, the bridge part 102,and the bridge part 103 connecting the third patterns 93 are turned intopatterns separated from one another, and therefore, it is possible toturn one of the first patterns 91 and the large cross-linking portion104 of the bridge part 103 connecting the first patterns 91, and thesecond patterns 92 and the large cross-linking portion 104 of the bridgepart 103 connecting the second patterns 92 into a mandrel pattern of awiring layout formed by the two-time sidewall method in which thesidewall is formed twice. Consequently, it is made possible to design awiring layout including the H-shaped pattern and separated pattern in awiring layout formed by the sidewall method easily. And therefore, it ispossible to aim at a high degree of integration of a wiring layout.

Next, a program for supporting a design of a wiring layout formed by thesidewall method is explained.

The program according to the embodiment causes a computer to executeprocedures shown below.

The program causes the computer to execute a procedure to display thebase pattern 90 on a display unit, for example, a display. As shown inFIG. 19, on the base pattern 90, a plurality of the first patterns 91extending in the Y direction and arranged at the first space in the Xdirection, a plurality of the second patterns 92 extending in the Ydirection and arranged respectively at the center between the firstpatterns 91, and a plurality of the third patterns 93 extending in the Ydirection and arranged respectively at the center between the firstpattern 91 and the second pattern 2 neighboring each other are provided.

It is preferable for the computer to, on the display unit, classify thefirst pattern 91, the second pattern 92, and the third pattern 93 bydifferent colors or hatch differently so that it is easy for a designerto make a layout.

Further, the program causes the computer to execute a procedure todisplay the line-cutting part 98, the bridge part 100, the bridge part102, and the bridge part 103.

The designer, via an input unit, for example a pointing device such as amouse, arranges the bridge part 100 in a predetermined position betweenthe two neighboring third patterns 93 sandwiching the one first pattern91 or the one second pattern 92 in the base pattern 90 displayed on thedisplay unit. After that, the computer executes a procedure to connectthe two third patterns 93 and at the same time, to replace the one firstpattern 91 or the one second pattern 92 with two patterns sandwichingthe bridge part 100 and not contacting the bridge part 100.

The designer, via the input unit, arranges the bridge part 102 in apredetermined position between the two neighboring third patterns 93sandwiching the one first pattern 91 or the one second pattern 92 in thebase pattern 90 displayed on the display unit. After that, the computerexecutes a procedure to replace the two third patterns 93 with a patternconnecting the two third patterns separated on the side in the +Ydirection and extending in the X direction and a pattern connecting thetwo third patterns separated on the side in the −Y direction andextending in the X direction, both patterns being separated from eachother in the Y direction and at the same time, to replace the one firstpattern 91 or the second pattern 92 intersecting the bridge part 102with two patterns sandwiching the bridge part 102 and not contacting thebridge part 102.

The designer, via the input unit, arranges the bridge part 103 in apredetermined position between the two neighboring second patterns 92sandwiching the one first pattern 91 and the two third patterns 93 inthe base pattern 90 displayed on the display unit. After that, thecomputer executes a procedure to replace the two third patterns 93connecting the two second patterns 92 and intersecting the bridge part103, respectively, with two patterns sandwiching the bridge part 103 butnot coming into the bridge part 103 and at the same time, to replace theone first pattern 91 with two patterns sandwiching the bridge part 103and not contacting the bridge part 103.

The designer, via the input unit, arranges the bridge part 103 in apredetermined position between the two neighboring first patterns 91sandwiching the one second pattern 92 and the two third patterns 93 inthe base pattern 90 displayed on the display unit. After that, thecomputer executes a procedure to replace the two third patterns 93connecting the two first patterns 91 and intersecting the bridge part103, respectively, with two patterns sandwiching the bridge part 103 andnot contacting the bridge part 103 and at the same time, to replace theone second pattern 92 with two patterns sandwiching the bridge part 103and not contacting the bridge part 103.

The designer, via the input unit, arranges the line-cutting part 98 in apredetermined position on the first pattern 91 in the base pattern 90displayed on the display unit. After that, the computer executes aprocedure to replace the first pattern 91 with two patterns separatedfrom each other in the Y direction and between which the bridge part100, the bridge part 102, or the bridge part 103 is not arranged.

The designer, via the input unit, arranges the line-cutting part 98 in apredetermined position on the second pattern 92 in the base pattern 90displayed on the display unit. After that, the computer executes aprocedure to replace the second pattern 92 with two patterns separatedfrom each other in the Y direction and between which the bridge part100, the bridge part 102, or the bridge part 103 is not arranged.

In this manner, it is possible for the program for supporting a designof a wiring layout formed by the two-time sidewall method in which thesidewall is formed twice to cause the computer to support the design ofthe wiring layout as shown in FIG. 22.

It may also be possible for the program to cause the computer to executea procedure to replace the patterns at a time when the designer clicksthe conversion button displayed on the display unit after arranging aplurality of parts (FIG. 49). As a result of that, it is possible forthe designer to arrange other parts in a state where each part isdisplayed, and therefore, making a layout is made easy.

Next, the effect of the program according to the embodiment isexplained.

According to the program according to the embodiment, it is possible tocause a computer to support a design of a wiring layout, and therefore,it is possible to reduce the time which the designer designs a wiringlayout that can be formed by the sidewall method.

In particular, it is almost impossible to create a design by consideringthe first-time sidewall from the mandrel in the two-time sidewall methodand further considering the second-time sidewall from the first-timesidewall. On the other hand, according to the program according to theembodiment, it is possible to design wiring mainly based on the finallayout. As a result of that, the design efficiency is improvedconsiderably.

Next, a method for manufacturing patterns by the two-time sidewallmethod is explained.

FIGS. 23A to 23D are process plan views illustrating a method formanufacturing patterns by the sidewall method according to the thirdembodiment and FIGS. 23E to 23H are process section views along B-B′surface shown in FIGS. 23A to 23D, respectively.

FIGS. 24 to 39 are process plan views illustrating the method formanufacturing patterns by the sidewall method according to the thirdembodiment.

As shown in FIGS. 23A and 23E, the insulating film 32 is formed on thesemiconductor substrate 31. After that, on the insulating film 32, afilm of a material that forms the mandrel 36 is formed. Further, on thefilm of the material that forms the mandrel 36, a resist film (not shownschematically) is formed. Next, the resist film is patterned by thelithography method. Patterning is performed by irradiating a mask (notshown schematically) placed on the resist film with exposure light. Atthis time, the width of a pattern formed on the resist film is theminimum processing dimension value of lithography in many cases.

The film of the material that forms the mandrel 36 is etched using thepatterned resist film as a mask. In this manner, the mandrel 36 isformed. The mandrel 36 is thinned by slimming according to thenecessity. Here, the width of the final mandrel 36 is substantially thesame as three times the length a in the wiring layout.

The sidewall 37 is formed on the side face of the mandrel 36. Thesidewall 37 is formed by, for example, removing the flat portion of thefilm of the material that forms the sidewall 37 by performinganisotropic etching and leaving the portion on the side face of themandrel 36 after forming the film of the material that forms thesidewall 37 on the semiconductor substrate 31 so as to cover the mandrel36. As a result of that, the sidewall 37 is formed into the shape of aclosed loop surrounding the mandrel 36 when viewed in the top view. Thethickness of the film of material that forms the sidewall 37 is reducedsmaller than ¼ of the space between the neighboring mandrels 36. Due tothis, a gap is formed between the sidewall 37 of the mandrel 36 and thesidewall 37 of the neighboring mandrel 36. Hereinafter, this gap isreferred to as the “inter-mandrel gap 38”. As a result of that, thelength of the inter-mandrel gap 38 is substantially the same as threetimes the length a in the wiring layout.

As shown in FIGS. 23B and 23F, the mandrel 36 is removed. Then, thesidewall 37 is slimmed according to the necessity. Here, the width ofthe final sidewall 37 is substantially the same as the length a in thewiring layout. After that, a second-time sidewall 45 is formed on theside face of the sidewall 37. As a result of that, the sidewall 45 isformed into the shape of two closed loops surrounding both sides of thesidewall 37. The sidewall 45 is formed by, for example, removing theflat portion of the film of material that forms the sidewall 45 byperforming anisotropic etching and leaving the portion on the side faceof the sidewall 45 after forming the film of material that forms thesidewall 45 on the semiconductor substrate 31 so as to cover thesidewall 37.

As shown in FIGS. 23C and 23G, the sidewall 37 is removed. Hereinafter,a gap between the sidewalls 45 in the region where the mandrel 36 existsis referred to as a “mandrel region 46”. Hereinafter, a region betweenthe sidewalls 45 in the inter-mandrel gap 38 is referred to as an“inter-mandrel region 47”. Hereinafter, a region between the sidewalls45 in the region where the sidewall 37 exists is referred to as a“sidewall-to-sidewall region 48”. Here, the width of thesidewall-to-sidewall region 48 is substantially the same as the length ain the wiring layout. After that, by performing etching on theinsulating film 32 using the sidewall 45 as a mask, the concave portion39 is formed by selectively removing the insulating film 32. The loopcut process is performed according to the necessity.

As shown in FIGS. 23D and 23H, the sidewall 45 is removed. After that,an electrically conductive material is deposited on the insulating film32 so as to fill in the concave portion 39. Then, the electricallyconductive material is flattened until the top face of the insulatingfilm 32 is exposed and the concave portion 39 is filled in with theelectrically conductive material. In this manner, the pattern 4 filledin the concave portion 39 is formed.

The length of the space between the patterns 40 neighboring in thedirection perpendicular to the direction in which the pattern 40 made ofthe electrically conductive material filled in the concave portion 39 issmaller than the length of the minimum space of a pattern that can beseparated by the lithography method used when patterning the resist film34.

The pattern 40 in the sidewall-to-sidewall region 48 is formed betweenthe pattern 40 in the mandrel region 46 and the pattern 40 in theinter-mandrel region 47.

Next, a method for forming the pattern 40 corresponding to the bridgepart 100, the bridge part 102, and the bridge part 103 is explained. Inthis method, the pattern 40 in the mandrel region 46 is cut and thepatterns 40 in the inter-mandrel region 47 and the sidewall-to-sidewallregion 48 are connected.

A method for forming the pattern 40 corresponding to the bridge part 100is explained.

As shown in FIG. 24A, as a pattern of the mandrel 36, between twopatterns extending in the Y direction, two patterns of the mandrel 36separated on the way are formed.

The two patterns of the mandrel 36 separated on the way are formed bythe lithography method using a mask in the same shape as the shape ofthe mandrel 36.

As shown in FIG. 24B, the width of the mandrel 36 is slimmed to W. Then,in the patterns of the mandrel 36 separated on the way, a space L3 inthe Y direction is set to a space that is filled in with the sidewall37, that is, to a length not more than twice the thickness of the filmmade of the material of the sidewall 37. Then, the sidewall 37 is formedon the side face of the mandrel 36. Due to this, the gap of theseparated mandrels 36 is filled in with the sidewall 37. Further, thesidewall 37 formed in the gap between the separated mandrels 36 connectswith the sidewalls 37 on both sides of the separated mandrels 36 andforms an H-shape.

As shown in FIG. 24C, the mandrel 36 is removed. At the portions wherethe separated mandrels 36 are removed, patterns of the separatedpatterns 40 are formed.

As shown in FIG. 25A, the sidewall 37 is slimmed. After that, on theside face of the sidewall 37, the sidewall 45 is formed.

As shown in FIG. 25B, the sidewall 37 is removed.

By performing the processes shown in FIGS. 23C and 23G, and 23D and 23H,in the sidewall-to-sidewall region 48, a pattern of the H-shaped pattern40 is formed as shown in FIG. 25C. In the mandrel regions 46, patternsof the separated patterns 40 are formed. In the inter-mandrel region 47,a pattern of the pattern 40 extending in the Y direction is formed.

Next, a method for forming the pattern 40 corresponding to the bridgepart 102 is explained. A case is explained where the pattern 40 in themandrel region 46 is cut and the two patterns in thesidewall-to-sidewall region 48 are connected.

As shown in FIG. 26A, as a pattern of the mandrel 36, between twopatterns extending in the Y direction, two patterns of the mandrels 36separated on the way are formed.

Next, as shown in FIG. 26B, the width of the mandrel 36 is slimmed to W.

The sidewall 37 is formed on the side face of the mandrel 36. The gapbetween the separated mandrels 36 is not filled in with the sidewall 37.

As shown in FIG. 26C, the mandrel 36 is removed.

Then, as shown in FIG. 27A, the sidewall 37 is slimmed. Here, a space L4between the sidewalls 37 separated in the Y direction is set to a spacethat is filled in with the sidewall 37 and the sidewall 45, that is, toa length not more than twice the thickness of the film made of thematerial of the sidewall 37 and not more than twice the thickness of thefilm made of the material of the sidewall 45. After that, on the sideface of the sidewall 37, the sidewall 45 is formed. Due to this, the gapbetween the separated mandrels 36 is closed by the sidewall 37 and thesidewall 45.

As shown in FIG. 27B, the sidewall 37 is removed.

By performing the processes shown in FIGS. 23C and 23G, and 23D and 23H,as shown in FIG. 27C, it is possible to form a pattern of the pattern 40corresponding to the bridge part 102. In the mandrel region 46, patternsof the separated patterns 40 are formed. In the inter-mandrel region 47,a pattern of the pattern 40 extending in the Y direction is formed.

Next, a method for forming the pattern 40 corresponding to the bridgepart 103 is explained. A case is explained where the pattern 40 in themandrel region 46 is cut and the patterns 40 in the inter-mandrel region47 is connected and at the same time, the two patterns 40 in thesidewall-to-sidewall region 48 are connected.

As shown in FIG. 28A, as a pattern of the mandrel 36, between twopatterns extending in the Y direction, two patterns of the mandrels 36separated on the way are formed.

As shown in FIG. 28B, the width of the mandrel 36 is slimmed to W.Further, in the patterns of the mandrels 36 separated on the way, aspace L5 in the Y direction is set to a space that is not filled in withthe sidewall 37 and the sidewall 45, that is, to a length not less thantwice the thickness of the film made of the material of the sidewall 37and not less than twice the thickness of the film made of the materialof the sidewall 45.

The sidewall 37 is formed on the side face of the mandrel 36. The gapbetween the separated mandrels 36 is not filled in with the sidewall 37.

As shown in FIG. 28C, the mandrel 36 is removed. At the portions fromwhich the separated mandrels 36 are removed, patterns of the separatedpatterns 40 are formed.

As shown in FIG. 29A, the sidewall 37 is slimmed. After that, thesidewall 45 is formed on the side face of the sidewall 37. The gap wherethe separated mandrels 36 are formed is not filled in with the sidewall37 and the sidewall 45. The gap where the separated mandrels 36 areformed couples with the gap between the sidewalls 45 extending in the Ydirection, forming an H-shape.

As shown in FIG. 29B, the sidewall 37 is removed.

The processes shown in FIGS. 23C and 23G, and 23D and 23H are performed.Due to this, it is possible to form the pattern 40 corresponding to thebridge part 103. In the mandrel region 46, patterns of the separatedpatterns 40 are formed. In the inter-mandrel region 47, a pattern of theH-shaped pattern 40 is formed.

Next, another method for forming the pattern 40 corresponding to thebridge part 100, the bridge part 102, and the bridge part 103 isexplained. This method is opposite to the method described previously inwhich the pattern 40 in the mandrel region 46 is cut and in this method,the pattern 40 in the inter-mandrel region 47 is cut.

First, a method for forming the pattern 40 corresponding to the bridgepart 100 is explained.

As shown in FIG. 30A, as a pattern of the mandrel 36, the mandrel 36extending in the Y direction is formed. When the pattern of theinter-mandrel region 47 is formed as two separated patterns, in thepatterns of the mandrels 36 sandwiching the region between the twoseparated patterns, the convex portion 42 protruding toward the regionbetween the two patterns is formed.

As shown in FIG. 30B, a space L6 between the convex portions 42 in themandrels 36 is set to a space that is filled in with the first-timesidewall 37, that is, to a space not more than twice the thickness ofthe sidewall 37 on the side face of the mandrel 36. After that, thesidewall 37 is formed on the side face of the mandrel 36. Due to this,the sidewalls formed on the side faces of the convex portions 42 areunited at that portion and the inter-mandrel gap 38 at that portion isseparated. The sidewall 37 having separated the inter-mandrel gap 38 andextending in the X direction and the sidewall 37 formed on the side faceof the mandrel 36 are coupled to form an H-shape.

As shown in FIG. 30C, the mandrel 36 is removed.

As shown in FIG. 31A, the sidewall 37 is slimmed and the sidewall 45 isformed on the side face of the sidewall 37.

As shown in FIG. 31B, the sidewall 37 is removed. At the portion fromwhich the sidewall 37 is removed, an H-shaped pattern is formed.

By performing the processes shown in FIGS. 23C and 23G, and 23D and 23H,as shown in FIG. 31C, it is possible to form a pattern of the H-shapedpattern 40 in the sidewall-to-sidewall region 48. In the mandrel region46, a pattern of the pattern 40 extending in the Y direction is formed.In the inter-mandrel region 47, patterns of the patterns 40 separated inthe Y direction are formed.

Next, a method for forming the pattern 40 corresponding to the bridgepart 102 is explained.

As shown in FIG. 32A, as a pattern of the mandrel 36, an H-shapedpattern is formed.

As shown in FIG. 32B, the mandrel 36 is slimmed and a width L7 of aportion extending in the X direction of the H-shaped mandrel 36 is setto a width that is filled in with the second-time sidewall 45, that is,to a length not more than twice the thickness of the film made of thematerial of the sidewall 45. Then, the sidewall 37 is formed on the sideface of the mandrel 36. In the +Y direction and the −Y direction of themandrel 36 extending in the X direction, patterns of the separatedinter-mandrel gaps 38 are formed.

As shown in FIG. 32C, the mandrel 36 is removed. Due to this, at theportion from which the mandrel 36 is removed, an H-shaped pattern isformed.

As shown in FIG. 33A, the sidewall 37 is slimmed. Then, the sidewall 45is formed on the side face of the sidewall 37. Due to this, the gapbetween the sidewalls 37 extending in the X direction is closed by thesidewall 37 and the sidewall 45.

As shown in FIG. 33B, the sidewall 37 is removed.

By performing the processes shown in FIGS. 23C and 23G, and 23D and 23H,as shown in FIG. 33C, it is possible to form the pattern 40corresponding to the bridge part 102. In the mandrel region 46, apattern of the pattern extending in the Y direction is formed. In theinter-mandrel region 47, patterns of the separated patterns 40 areformed.

Next, a method for forming the pattern 40 corresponding to the bridgepart 103 is explained.

As shown in FIG. 34A, as a pattern of the mandrel 36, an H-shapedpattern is formed.

Next, as shown in FIG. 34B, a width L8 of a portion extending in the Xdirection in the H-shaped mandrel 36 is set to a width that is notfilled in with the second-time sidewall 45, that is, to a length notless than twice the thickness of the film made of the material of thesidewall 45. Then, the sidewall 37 is formed on the side face of themandrel 36. In the +Y direction and the −Y direction of the mandrel 36extending in the X direction, patterns of the separated inter-mandrelgaps 38 are formed.

As shown in FIG. 34C, the mandrel 36 is removed. Due to this, at theportion from which the mandrel 36 is removed, an H-shaped pattern isformed.

As shown in FIG. 35A, the sidewall 37 is slimmed. Then, the sidewall 45is formed on the side face of the sidewall 37. In the separatedinter-mandrel gap 38, a region extending in the X direction that is notclosed by the sidewall 37 or the sidewall 45 is formed. This region andthe gap in the sidewall extending in the Y direction are coupled to foaman H-shaped pattern.

As shown in FIG. 35B, the sidewall 37 is removed.

By performing the processes shown in FIGS. 23C and 23G, and 23D and 23H,as shown in FIG. 35C, it is possible to form the pattern 40corresponding to the bridge part 103. In the mandrel region 46, apattern of the H-shaped pattern is formed. In the inter-mandrel region47, patterns of the separated patterns 40 are formed.

Next, a method for forming a pattern corresponding to the line-cuttingpart 98, that is, a separated pattern is explained.

First, a method for cutting the pattern 40 in the mandrel region 46 isexplained.

As shown in FIG. 36A, when the pattern of the mandrel 36 is separatedinto two patterns, as a pattern of the mandrel 36, the mandrel 36extending in the Y direction is formed. Then, the portion correspondingto the region of the mandrel 36 to be separated is thinned.

As shown in FIG. 36B, the sidewall 37 is formed on the side face of themandrel 36. The space between the sidewalls 37 formed on the side faceson both sides of the thinned portion of the mandrel 36 is formed thin.

As shown in FIG. 36C, the mandrel 36 is removed.

The sidewall 37 is slimmed. Then, a space L9 between the sidewalls 37formed on the side faces on both sides of the thinned portion of themandrel 36 is set to a width that is filled in with the sidewall 45,that is, to a length not more than twice the thickness of the film madeof the material of the sidewall 45.

As shown in FIG. 37A, the sidewall 45 is formed on the side face of thesidewall 37.

Due to this, the gap between the sidewalls 37 at the portions locatedbetween the two separated patterns is filled in with the sidewall 45.

As shown in FIG. 37B, the sidewall 37 is removed.

After that, by performing the processes shown in FIGS. 23C and 23G, and23D and 23H, as shown in FIG. 37C, it is possible to form a pattern ofthe pattern 40 corresponding to the pattern of the mandrel 36 separatedin the Y direction. Further, in the pattern formed in thesidewall-to-sidewall region 48, the convex portion 44 protruding towardthe region where the mandrel 36 is thinned is formed.

Next, in the method for forming a pattern corresponding to a separatepattern by the sidewall method, a method for cutting the pattern 40 inthe inter-mandrel region 47 is explained.

As shown in FIG. 38A, as a pattern of the mandrel 36, the mandrel 36extending in the Y direction is formed. When the pattern of the mandrel36 is formed as two separated patterns, in the patterns of the mandrels36 sandwiching the region between the two separated patterns, the convexportion 42 protruding toward the region between the two patterns isformed. A space L10 between the convex portions 42 in the mandrels 36 isset to a width that is filled in with the sidewall 37 and the sidewall45, that is, to a width not more than twice the thickness of the filmmade of the material of the sidewall 37 and twice the thickness of thefilm made of the material of the sidewall 45.

As shown in FIG. 38B, the sidewall 37 is formed on the side face of themandrel 36.

As shown in FIG. 38C, the mandrel 36 is removed.

As shown in FIG. 39A, the sidewall 45 is formed on the side face of thesidewall 37. Due to this, the sidewalls 45 formed on the side faces ofthe convex portions 42 are united at the portion and the inter-mandrelgap 38 at that portion is separated.

As shown in FIG. 39B, the sidewall 37 is removed.

By performing the processes shown in FIGS. 23C and 23G, and 23D and 23H,as shown in FIG. 39C, it is possible to form the pattern of the pattern40 in the inter-mandrel region 47 separated in the Y direction. Further,in the pattern formed in the sidewall-to-sidewall region 48, the convexportion 44 protruding toward the direction in which the convex portion42 is formed is formed.

Next, a method for manufacturing a semiconductor device based on awiring layout including the line-cutting part 98 and the bridge parts100, 102, and 103 described previously is explained.

As shown in FIG. 22 described previously, in the wiring layout, themandrel 36 is formed on the insulating film 32 using one of the firstpatterns 91 and the large cross-linking portion 104 of the bridge part103 connecting the first patterns 91, and the second patterns 22 and thelarge cross-linking portion 104 of the bridge part 103 connecting thesecond patterns 22 as a pattern of the mandrel 36.

For example, the mandrel 36 is formed on the insulating film 32 usingthe first patterns 11 and the large cross-linking portion 104 of thebridge part 103 connecting the first patterns 91 in FIG. 22 in theembodiment as a pattern of the mandrel 36.

At the portion (the region 105) that is turned into patterns of theseparated mandrels 36, as shown in FIG. 36A, the width of the mandrel 36in the region between the two separated patterns is thinned.

At the portion (the region 106) corresponding to the bridge part 100, asshown in FIG. 30A described previously, in the patterns of the mandrels36 sandwiching the region between the two separated patterns, the convexportions 42 protruding toward the region between the two patterns areformed.

At the portion (the region 107) corresponding to the bridge part 102, inthe pattern of the separated mandrel 36, the space L4 in the Y directionis set to a space that is filled in with the sidewall 37 and thesidewall 45, that is, to a length not more than the thickness of thefilm made of the material of the sidewall 37 and the thickness of thefilm made of the material of the sidewall 45.

At the portion (the region 108) corresponding to the bridge part 103, asa pattern of the mandrel 36, an H-shaped pattern is formed. The width L8of the portion extending in the X direction in the H-shaped mandrel 36is set to a width that is not filled in with the second-time sidewall45, that is, to a length not less than twice the thickness of the filmmade of the material of the sidewall 45.

The processes shown in FIGS. 23B and 23F, FIGS. 23C and 23G, and FIGS.23D and 23H are performed. At this time, in the region 105, theprocesses as shown in FIG. 36 and FIG. 37 are performed. In the region106, the processes as shown in FIG. 30 and FIG. 31 are performed. In theregion 107, the processes as shown in FIG. 26 and FIG. 27 are performed.In the region 108, the processes as shown in FIG. 34 and FIG. 35 areperformed.

In this manner, as shown in FIG. 40, a semiconductor device 3 includingthe pattern 40 formed based on the wiring layout shown in FIG. 22 ismanufactured.

Next, the effect of the method for manufacturing patterns by thetwo-time sidewall method according to the embodiment is explained.

According to the method for manufacturing patterns by the two-timesidewall method according to the embodiment, it is possible tomanufacture the semiconductor device 3 including the pattern 40 of theH-shape pattern and the separated pattern 40.

Further, by using one of the patterns of the mandrel 36 and theinter-mandrel gap 38, it is possible to form the H-shaped pattern 40 andthe separated pattern 40. Consequently, it is made possible to design awiring layout including a wiring space narrower than the minimum valueof the space by the resolution of lithography easily. And therefore, itis possible to manufacture a semiconductor device including highlyintegrated patterns.

Next, the semiconductor device 3 according to the third embodiment isexplained.

FIG. 40 is a plan view illustrating the semiconductor device accordingto the third embodiment.

As shown in FIG. 23 and FIG. 40, the semiconductor device 3 includes thesemiconductor substrate 31 and the pattern 40 provided on thesemiconductor substrate 31.

In the semiconductor device 3, a plurality of patterns 75 correspondingto the plurality of the first patterns 91 extending in the Y direction,a plurality of patterns 76 corresponding to the plurality of the secondpatterns 92 extending in the Y direction, a plurality of patterns 77corresponding to the plurality of the third patterns 93 extending in theY direction, a pattern 78 extending in the X direction and correspondingto the large cross-linking portion 104 of the bridge part 103 connectingthe first patterns 91, and a plurality of patterns 79 extending in the Xdirection and corresponding to the bridge part 100 and the bridge part102 connecting the third patterns 93 are provided.

If a plurality of first lines extending in the Y direction and arrangedat a space ½ of the first space in the X direction are supposed in theXY plane and integers from one are assigned to the first lines in orderfrom the end, the patterns 75 are arranged in the odd-numbered firstlines and the patterns 76 in the even-numbered first lines. Further, ifa plurality of second lines extending in the Y direction and providedone by one between the first lines are supposed, the patterns 77 arearranged in the second lines.

The pattern 78 connects the patterns 75. The pattern 79 connects thepatterns 77. Then, the pattern 75 and the pattern 78 are separated fromeach other and the pattern 76, the pattern 77, and the pattern 79 areseparated from one another.

In the region 105, two of the patterns 75 are arranged in the same line,separated from each other in the Y direction, and the pattern 79 is notarranged therebetween.

Then, in the X direction, in the two patterns 76 sandwiching a region 80between the two patterns 75, the convex portion 44 protruding toward theregion 80 is formed.

Next, the effect of the method for manufacturing the semiconductordevice 3 according to the embodiment is explained.

According to the method for manufacturing the semiconductor device 3according to the embodiment, the H-shaped pattern 40 and the separatedpattern 40 are included and the wiring space narrower than the minimumvalue of the space by the resolution of lithography is included, andtherefore, it is possible to highly integrate the semiconductor device.

Fourth Embodiment

Next, a fourth embodiment is explained.

First, a method for designing a wiring layout that is formed by thesidewall method according to the fourth embodiment is explained.

FIG. 41 is a plan view illustrating a base pattern used in the methodfor designing a wiring layout according to the fourth embodiment.

FIGS. 42A to 42H are plan views illustrating layout parts used in thefourth embodiment, wherein FIG. 42A shows a line-cutting part, FIGS.42B, 42D, and 42F show Y bridge parts, FIGS. 42C, 42E, and 42G show Xbridge parts, and FIG. 42H shows a contact fringe.

FIG. 43 is a plan view illustrating a state where the bridge parts andthe contact fringe are arranged on the base pattern in the fourthembodiment.

As shown in FIG. 41, on a base pattern 110 according to the embodiment,a first pattern 111 formed by a plurality of patterns extending in onedirection and in a direction perpendicular to the one direction isprovided.

The first pattern 111 includes patterns 111 a extending in the Ydirection and arranged at the first space in the X direction andpatterns 111 b extending in the X direction and arranged at the secondspace in the Y direction. The patterns 111 a and the patterns 111 b forma lattice. At the intersection of the lattices and at the middle pointbetween neighboring intersections on the pattern 111 a and the pattern111 b, a first point 111 c is provided. That is, the pattern 111 a andthe pattern 111 b are formed so as to connect the three first points 111c by a straight line and form a lattice by sharing the first point 111 cat the end portion. The first pattern 111 a and the first pattern 111 bare together referred to as the first pattern 111 in some cases.

On the base pattern 110 a plurality of second points 112 are provided.The plurality of the second points 112 are arranged in a matrix at thefirst space in the X direction and at the second space in the Ydirection. However, the second points 112 are arranged at a spaceshifted by ½ of the first space in the X direction with respect to thefirst pattern 111 a. Further, the second points 112 are arranged at aspace shifted by ½ of the second space in the Y direction with respectto the first pattern 111 b.

On the base pattern 110, a plurality of third points 113 c are provided.The plurality of the third points 113 c are arranged in a matrix at aspace ½ of the first space in the X direction and at a space ½ of thesecond space in the Y direction. However, the third points 113 c arearranged at a space shifted by ¼ of the first space in the X directionwith respect to the first point 111 c or the second point 112. Further,the third points 113 c are arranged at a space shifted by ¼ of thesecond space in the Y direction with respect to the first point 111 c orthe second point 112. Further, the third points 113 are arranged infours in one lattice formed by the first pattern 111 a and the firstpattern 111 b. The four third points 113 c are connected by a thirdpattern 113 b extending in the X direction and a third pattern 113 aextending in the Y direction so as to surround the second point. Thethird pattern 113 a and the third pattern 113 b are together referred toas the third pattern 113 in some cases. At the center portion of thefirst pattern 111 and the third pattern 113, the second point 112 isarranged.

In the embodiment, the first space and the second space are made thesame. Further, the width of the first pattern 111 and the third pattern113 is set to a length ⅛ of the first space. This length is referred toas the length a. Furthermore, the shape of the first point 111 c, thesecond point 112, and the third point 113 c are formed into a square oneside of which has the length a.

As shown in FIG. 42A, the line-cutting part 98 includes the rectangularportion 99. As shown in FIG. 42B, a Y bridge part 120 includes a Ycross-linking portion 121 and the two rectangular portions 99. The Ycross-linking portion 121 extends in the Y direction. The length in theY direction is set to a length five times the length a (5 a). The widthof the Y cross-linking portion 121 is set to the length a. Therectangular portion 99 is provided at the center on the side face in theX direction of the Y cross-linking portion 121.

As shown in FIG. 42C, an X bridge part 122 includes an X cross-linkingportion 123 and the two rectangular portions 99. The X cross-linkingportion 123 extends in the X direction. The length in the X direction ofthe X cross-linking portion 123 is set to a length five times the lengtha (5 a). The width of the X cross-linking portion 123 is set to thelength a. The rectangular portion 99 is provided at the center on theside face in the Y direction of the X cross-linking portion 123.

As shown in FIG. 42D, a Y bridge part 124 includes the two Ycross-linking portions 121 and the five rectangular portions 99. The twoY cross-linking portions 121 are arranged side by side in the Xdirection. At the center portion and both ends between the two Ycross-linking portions 121, the rectangular portion 99 is provided. Atthe center portion on the side face facing in the +Y direction of the Ycross-linking portion 121 on the side in the +X direction, therectangular portion 99 is provided. At the center portion on the sideface facing in the −Y direction of the Y cross-linking portion 121 onthe side in the −Y direction, the rectangular portion 99 is provided.

As shown in FIG. 42E, an X bridge part 125 includes the two Xcross-linking portions 123 and the five rectangular portions 99. The twoX cross-linking portions 123 are arranged in tandem in the Y direction.At the center portion and both ends between the two X cross-linkingportions 123, the rectangular portion 99 is provided. At the centerportion on the side face facing in the +Y direction of the Xcross-linking portion 123 on the side in the +Y direction, therectangular portion 99 is provided. At the center portion on the sideface facing in the −Y direction of the X cross-linking portion 123 onthe side in the −Y direction, the rectangular portion 99 is provided.

As shown in FIG. 42F, a Y bridge part 126 includes one large Ycross-linking portion 127, the two Y cross-linking portions 121, and theeight rectangular portions 99. The one large Y cross-linking portion 127extends in the Y direction. The length in the Y direction of the large Ycross-linking portion 127 is set to a length nine times the length a (9a). The width of the large Y cross-linking portion 127 is set to thelength a. On the side in the +X direction and on the side in the −Xdirection of the large Y cross-linking portion 127, the Y cross-linkingportion 121 is provided. The center in the Y direction of the large Ycross-linking portion 127 and the center in the Y direction of the Ycross-linking portion 121 agree in the Y direction. Between the Ycross-linking portion 121 on the side in the +X direction of the large Ycross-linking portion 127 and the large Y cross-linking portion 127, therectangular portion 99 is provided at the center portion and both endson the side face of the Y cross-linking portion 121 on the side in the+X direction. Between the Y cross-linking portion 121 on the side in the−X direction of the large Y cross-linking portion 127 and the large Ycross-linking portion 127, the rectangular portion 99 is provided at thecenter portion and both ends on the side face of the Y cross-linkingportion 121 on the side in the −X direction. At the center portion onthe side face facing in the +X direction of the Y cross-linking portion121 on the side in the +X direction, the rectangular portion 99 isprovided. At the center portion on the side face facing in the −Xdirection of the Y cross-linking portion 121 on the side in the −Xdirection, the rectangular portion 99 is provided.

As shown in FIG. 42G, an X bridge part 128 includes one large Xcross-linking portion 129, the two X cross-linking portions 123, and theeight rectangular portions 99. The one large X cross-linking portion 129extends in the X direction. The length in the X direction of the large Xcross-linking portion 129 is set to a length nine times the length a (9a). The width of the large X cross-linking portion 129 is set to thelength a. On the side in the +Y direction and on the side in the −Ydirection of the large X cross-linking portion 129, the X cross-linkingportion 123 is provided. The center in the X direction of the large Xcross-linking portion 129 and the center in the X direction of the Xcross-linking portion 123 agree in the X direction. Between the Xcross-linking portion 123 on the side in the +Y direction of the large Xcross-linking portion 129 and the large X cross-linking portion 129, therectangular portion 99 is provided at the center portion and both endson the side face of the X cross-linking portion 123 on the side in the+Y direction. Between the X cross-linking portion 123 on the side in the−Y direction of the large X cross-linking portion 129 and the large Xcross-linking portion 129, the rectangular portion 99 is provided at thecenter portion and both ends on the side face of the X cross-linkingportion 123 on the side in the −Y direction. At the center portion onthe side face facing in the +Y direction of the X cross-linking portion123 on the side in the +Y direction, the rectangular portion 99 isprovided. At the center portion on the side face facing in the −Ydirection of the X cross-linking portion 123 on the side in the −Ydirection, the rectangular portion 99 is provided.

As shown in FIG. 42H, a contact fringe 130 includes a contact portion140, the two Y cross-linking portions 121, the two X cross-linkingportions 123, and 16 rectangular portions 99. The contact portion 140 isformed into the shape of a rectangular and the length of the side in theY direction is set to a length nine times the length a (9 a) and thelength of the side in the X direction is set to a length nine times thelength a (9 a). On the side in the +X direction and on the side in the−X direction of the contact portion 140, the Y cross-linking portion 121is provided. The center in the Y direction of the contact portion 140and the center in the Y direction of the Y cross-linking portion 121agree in the Y direction. Between the Y cross-linking portion 121 on theside in the +X direction of the contact portion 140 and the contactportion 140, the rectangular portion 99 is provided at the centerportion and both ends on the side face of the Y cross-linking portion121 on the side in the +X direction. Between the Y cross-linking portion121 on the side in the −X direction of the contact portion 140 and thecontact portion 140, the rectangular portion 99 is provided at thecenter portion and both ends on the side face of the Y cross-linkingportion 121 on the side in the −X direction. At the center portion onthe side face facing in the +Y direction of the Y cross-linking portion121 on the side in the +X direction, the rectangular portion 99 isprovided. At the center portion on the side face facing in the −Ydirection of the Y cross-linking portion 121 on the side in the −Xdirection, the rectangular portion 99 is provided.

On the side in the +Y direction and on the side in the −Y direction ofthe contact portion 140, the X cross-linking portion 123 is provided.The center in the X direction of the contact portion 140 and the centerin the X direction of the X cross-linking portion 123 agree in the Xdirection. Between the X cross-linking portion 123 on the side in the +Ydirection of the contact portion 140 and the contact portion 140, therectangular portion 99 is provided at the center portion and both endson the side face of the X cross-linking portion 123 on the side in the+Y direction. Between the X cross-linking portion 123 on the side in the−Y direction of the contact portion 140 and the contact portion 140, therectangular portion 99 is provided at the center portion and both endson the side face of the X cross-linking portion 123 on the side in the−Y direction. At the center portion on the side face facing in the +Ydirection of the X cross-linking portion 123 on the side in the +Ydirection, the rectangular portion 99 is provided. At the center portionon the side face facing in the −Y direction of the X cross-linkingportion 123 on the side in the −Y direction, the rectangular portion 99is provided.

As shown in FIG. 43, the Y bridge part 120 is arranged between the thirdpoints 113 c neighboring in the Y direction. The X bridge part 122 isarranged between the third points 113 c neighboring in the X direction.

Further, the Y bridge part 126 is arranged between the second points 112neighboring in the Y direction. The X bridge part 128 is arrangedbetween the second points 112 neighboring in the X direction.

Furthermore, the contact fringe 130 is arranged so as to span the firstpoint 111 c the first space distant in the X direction with the onefirst point 111 c as a reference and the first point the second spacedistant in the Y direction with the one first point 111 c as areference.

Still furthermore, the contact fringe 130 is arranged so as to span thesecond point 112 the first space distant in the X direction with the onesecond point 112 as a reference and the second point the second spacedistant in the Y direction with the one second point 112 as a reference.

If necessary, the line-cutting part 98 is arranged on the portion to beseparated in the first pattern 111, the large Y cross-linking portion127, and the large X cross-linking portion 129. Further, the Y bridgepart 124 and the X bridge part 125 are arranged between the thirdpatterns 113 b or between the third patterns 113 a.

In this manner, a wiring layout formed by the sidewall method is made.

Next, the effect of the method for designing a wiring layout accordingto the embodiment is explained.

According to the method for designing a wiring layout according to theembodiment, patterns arranged in the form of a two-dimensional latticeare included as the base pattern 110, and therefore, it is made possibleto create a freer design not limited to a pattern extending in onedirection and it is possible to aim at a high degree of integration ofthe wiring layout.

Further, according to the embodiment, the first pattern 111 and thelarge Y cross-linking portion 127 connected to the first pattern 111,the large X cross-linking portion 129 and the contact portion 140, thelarge Y cross-linking portion 127 connected to the second point 112, thelarge X cross-linking portion 129, and the contact portion 140, and thethird pattern 113 and the Y cross-linking portion 121 the Xcross-linking portion 123 connected to the third pattern 113 are turnedinto patterns separated from one another. Consequently, it is possibleto make a wiring layout formed by the sidewall method.

Next, a base pattern according to a modified example of the fourthembodiment is explained.

FIG. 44 is a plan view illustrating a base pattern in the modifiedexample of the fourth embodiment.

As shown in FIG. 44, on the base pattern 124, the first point 111 c, thesecond point 112, and the third point 113 c are provided.

In predetermined positions in the base pattern 124, the parts shown inFIGS. 42A to 42H are arranged. Due to this, a wiring layout is made.

Next, the effect of the modified example is explained.

According to the modified example, the first point 111 c and the thirdpoint 113 c are used. It is made possible to design a wiring layout notlimited to a lattice pattern and it is possible to aim at a high degreeof integration of the wiring layout easily.

Next, a program for supporting a design of a wiring layout formed by thesidewall method is explained.

The program according to the embodiment causes a computer to executeprocedures shown below.

The program causes the computer to execute a procedure to display thebase pattern 110 on the display unit.

Further, the program causes the computer to execute a procedure todisplay the line-cutting part 98, the Y bridge part 120, the Y bridgepart 124, the Y bridge part 126, the X bridge part 122, the X bridgepart 125, the X bridge part 128, and the contact fringe 130 on thedisplay unit. It is preferable for the computer to classify the firstpoint 111 c to the third point 113 c by different colors or hatchdifferently to make it easy for a designer to make a layout. Similarly,it is preferable for the computer to classify the first pattern 111, thethird pattern, and the second point by different colors or hatchdifferently to make it easy for the designer to make a layout.

The designer, via the input unit, arranges the Y bridge part 120 in apredetermined position between the two third points 113 c adjacent toeach other in the Y direction in the base pattern 110 displayed on thedisplay unit. At this time, the computer executes a procedure to connectthe two third points 113 c and at the same time, to replace the onefirst pattern 111 b with two patterns sandwiching the Y bridge part 120and not contacting the bridge part 120.

The designer, via the input unit, arranges the X bridge part 122 in apredetermined position between the two third points 113 c adjacent toeach other in the X direction in the base pattern 110 displayed on thedisplay unit. At this time, the computer executes a procedure to connectthe two third points 113 c and at the same time, to replace the onefirst pattern 111 a with two patterns sandwiching the Y bridge part 122and not contacting the Y bridge part 122.

The designer, via the input unit, arranges the Y bridge part 126 in apredetermined position between the two second points 112 adjacent toeach other in the Y direction in the base pattern 110 displayed on thedisplay unit. At this time, the computer executes a procedure to connectthe two second points 112 and replace the two third patterns 113 bintersecting the Y bridge part 126 with two patterns sandwiching the Ybridge part 126 and not contacting the Y bridge part 126 and at the sametime, to replace the one first pattern 111 b with two patternssandwiching the Y bridge part 126 and not contacting the Y bridge part126.

The designer, via the input unit, arranges the Y bridge part 128 in apredetermined position between the two second points 112 adjacent toeach other in the X direction in the base pattern 110 displayed on thedisplay unit. At this time, the computer executes a procedure to connectthe two second points 112 and replace the two third patterns 113 aintersecting the Y bridge part 128 with two patterns sandwiching the Ybridge part 128 and not contacting the Y bridge part 128 and at the sametime, to replace the one first pattern 111 a with two patternssandwiching the Y bridge part 128 and not contacting the Y bridge part128.

The designer, via the input unit, arranges the contact fringe 130 so asto span the first point 111 c the first space distant in the X directionand the first point 111 c the second space distant in the Y directionwith the one first point 111 c in the base pattern 110 displayed on thedisplay unit as a reference. At this time, the computer executes aprocedure to replace the contact fringe 130 with a pattern covering thefirst point 111 c the first space distant in the X direction and thefirst point 111 c the second space distant in the Y direction with thefirst point 111 c as a reference.

The designer, via the input unit, arranges the contact fringe 130 so asto span the second point 112 the first space distant in the X directionand the second point 112 the second space distant in the Y directionwith the one second point 112 in the base pattern 10 displayed on thedisplay unit as a reference. At this time, the computer executes aprocedure to replace the contact fringe 130 with a pattern covering thesecond point 112 the first space distant in the X direction and thesecond point 112 the second space distant in the Y direction with thesecond point 112 as a reference.

The designer, via the input unit, arranges the line-cutting part 98 atportions to be separated in the first pattern 111, the large Ycross-linking portion 127, and the large X cross-linking portion 129. Atthis time, the computer executes a procedure to replace the portionswith two separated patterns.

In this manner, it is possible for the program for supporting a designof a wiring layout formed by the sidewall method in which the sidewallis formed twice to cause a computer to support the design of the wiringlayout as shown in FIG. 43.

It may also be possible for the program to cause the computer to executea procedure to replace the patterns at a time when the designer clicksthe conversion button displayed on the display unit after arranging aplurality of parts (FIG. 49). As a result of that, it is possible forthe designer to arrange other parts in a state where each part isdisplayed, therefore, making a layout is made easy.

Next, the effect of the program for supporting a design of a wiringlayout according to the embodiment is explained.

According to the program according to the embodiment, it is possible tocause a computer to support a design of a wiring layout, and therefore,it is possible to reduce the time which designer designs a wiring layoutformed by the sidewall method.

In particular, it is almost impossible to create a design by consideringthe first-time sidewall from the mandrel in the two-time sidewall methodand further considering the second-time sidewall from the first-timesidewall. On the other hand, according to the program according to theembodiment, it is possible to design wiring mainly based on the finallayout. As a result of that, the design efficiency is improvedconsiderably.

Next, a method for manufacturing a semiconductor device includingpatterns formed based on a wiring layout by the sidewall method in whichthe sidewall is formed twice is explained.

FIG. 45 is a plan view illustrating the method for manufacturing asemiconductor device according to the fourth embodiment.

As shown in FIG. 43, in the wiring layout described previously, themandrel 36 is formed on the insulating film 32 using the first pattern111 and the contact portion 140 connected to the first pattern 111 as apattern of the mandrel 36.

The sidewall 37 is formed on the side face of the mandrel 36.

The mandrel 36 is removed by etching.

The processes in FIGS. 5B and 5F, FIGS. 5C and 5G, and FIGS. 5D and 5Hare performed.

In this manner, a semiconductor device 4 including the pattern 40 formedbased on the wiring layout is manufactured as shown in FIG. 45.

Next, the effect of the method for manufacturing a semiconductor deviceaccording to the embodiment is explained.

It is made possible to design a wiring layout including a wiring spacenarrower than the minimum value of space by the resolution oflithography easily. And therefore, it is possible to manufacture asemiconductor device including highly integrated patterns.

Next, the semiconductor device 4 according to the embodiment isexplained.

The semiconductor device 4 includes a semiconductor substrate and thepattern 40 provided on the semiconductor substrate. In order to explainthe semiconductor device 4, the XY rectangular coordinate system isadopted. In the XY rectangular coordinate system, the upward directionin the figure is set to the +Y direction and the opposite direction the−Y direction as in the XY rectangular coordinate system adopted in orderto explain the base pattern 60 in FIG. 41. The direction 90 degreesrotated clockwise from the +Y direction is set to the +X direction andthe opposite direction the −X direction.

In the semiconductor device 4, a plurality of patterns 131 correspondingto the first pattern 111 a extending in the Y direction, a plurality ofpatterns 132 corresponding to the large Y cross-linking portion 127connecting the second points 112, and a plurality of patterns 133corresponding to the third pattern 113 a extending in the Y directionand the Y cross-linking portion 121 are provided. Further, in thesemiconductor device 4, a plurality of patterns 134 corresponding to thefirst pattern 111 b extending in the X direction, a plurality ofpatterns 135 corresponding to the large X cross-linking portion 129connecting the second points 112, and a plurality of patterns 136corresponding to the third pattern 113 b extending in the X directionand the X cross-linking portion 123.

If a plurality of first lines extending in the Y direction and arrangedat a space ½ of the first space in the X direction are supposed in theXY plane and integers from one are assigned to the first lines in orderfrom the end, and if a plurality of second lines extending in the Xdirection, arranged at a space ½ of the second space in the Y direction,and intersecting the first lines are supposed in the XY plane andintegers from one are assigned to the second lines in order from theend, the patterns 131 are arranged in the odd-numbered first lines andthe patterns 132 in the even-numbered first lines. The patterns 134 arearranged in the odd-numbered second lines and the patterns 135 in theeven-numbered second lines.

If a plurality of third lines extending in the Y direction and arrangedone by one between the first lines adjacent to each other are supposed,the patterns 133 are arranged in the third lines. Further, if aplurality of fourth lines extending in the X direction and arranged oneby one between the second lines adjacent to each other are supposed, thepatterns 136 are arranged in the fourth lines.

Then, at least one of the patterns 131 connects with the pattern 134 andat least one of the patterns 132 connects with the pattern 135. Further,at least one of the patterns 133 connects with the pattern 136.

Furthermore, the pattern 131 and the pattern 134, the pattern 132 andthe pattern 135, and the pattern 133 and the pattern 136 are separatedfrom one another.

Next, the method for manufacturing a semiconductor device according tothe embodiment is explained.

According to the semiconductor device 4 according to the embodiment, theH-shaped pattern 40 and the separated pattern 40 are included and awiring space narrower than the minimum value of space by the resolutionof lithography is included, and therefore, it is possible to increasethe degree of integration of the semiconductor device.

Fifth Embodiment

Next, a fifth embodiment is explained.

FIGS. 46A to 46D are plan views illustrating constituent units of a basepattern in the fifth embodiment.

FIGS. 47A and 47B are plan views illustrating constituent units of thebase pattern in the fifth embodiment and FIG. 47C is a plan viewillustrating a wiring layout in the fifth embodiment.

FIG. 48 is a plan view illustrating a constituent unit of the basepattern in the fifth embodiment.

As shown in FIGS. 46A to 46F, the constituent units of a base pattern200 in the embodiment are formed into the shape of a matrix or lattice.Then, the constituent units in a matrix or lattice are selectedaccording to the number of times the sidewall is formed in the sidewallmethod.

First, the constituent units of the base pattern 200 to be used in adesign of a wiring layout in the sidewall method in which the sidewallis formed once are explained.

As shown in FIG. 46A, the constituent unit of the base pattern 200includes a first point 201 and four second points 202 provided,respectively, with the first point 201 as a reference, in a position thefirst space distant in the +X direction and the second space distant inthe +Y direction, in a position the space distant in the −X directionand the second space distant in the +Y direction, in a position thefirst space distant in the +X direction and the second space distant inthe −Y direction, and in a position the first space distant in the −Xdirection and the second space distant in the −Y direction.

As shown in FIG. 46C, the constituent unit of the base pattern 200 maybe a unit surrounded by two patterns the distance of which is the firstspace with the first point 201 as a reference, extending in the Ydirection, and connecting the second points 202, and two patterns thedistance of which is the second space with the first point 201 as areference, extending in the X direction, and connecting the secondpoints 202. By using the base pattern 200 on which such constituentunits are arrayed two-dimensionally, a wiring layout formed by thesidewall method is designed. Then, a pattern is formed by the sidewallmethod using one of the first point 201 and the pattern connecting thesecond points 202 as a mandrel. In other words, it can be said that thefirst point 201 and the pattern connecting the second points 202 aredifferentiated by two different colors.

Next, a case of the sidewall method in which the sidewall is formedtwice is explained.

As shown in FIG. 46B, constituent units of the base pattern 200 are theunits described previously to which third points 203 as follows arefurther added. That is, the eight third points 203 provided,respectively, with the first point as a reference, in a position twicethe first space distant in the +X direction, in a position twice thefirst space distant in the +X direction and twice the second spacedistant in the +Y direction, in a position twice the first space distantin the +X direction and twice the second space distant in the −Ydirection, in a position twice the second space distant in the +Ydirection, in a position twice the second space distant in the −Ydirection, in a position twice the first space distant in the −Xdirection, in a position twice the first space distant in the −Xdirection and twice the second space distant in the +Y direction, and ina position twice the first space distant in the −X direction and twicethe second space distant in the −Y direction are added.

As shown in FIG. 46D, the constituent unit of the base pattern 200 maybe a unit surrounded by two patterns the distance of which is twice thefirst space with the first point as a reference, extending in the Ydirection, and connecting the third points 203, and two patterns thedistance of which is twice the second space with the first point as areference, extending in the X direction, and connecting the third points203 in addition to the constituent unit of FIG. 46C. By using the basepattern 200 on which such constituent units are arrayedtwo-dimensionally, a wiring layout by the sidewall method in which thesidewall is formed twice is designed. A pattern is formed by thesidewall method using one of the first point and the pattern connectingthe third points 203 as a mandrel. In other words, it can be said thatthe first point 201, the pattern connecting the second points 202, andthe pattern connecting the third points 203 are differentiated with eachother by three different colors.

Next, a case of the sidewall method in which the sidewall is formedthree times is explained.

As shown in FIG. 47A, constituent units of the base pattern 200 are theconstituent units shown in FIG. 46B to which fourth points 204 and fifthpoints 205 as follows are further added.

That is, the 12 fourth points 204 provided, respectively, with the firstpoint 201 as a reference, in a position three times the first spacedistant in the +X direction and the second space distant in the +Ydirection, in a position three times the first space distant in the +Xdirection and three times the second space distant in the +Y direction,in a position three times the first space distant in the +X directionand the second space distant in the −Y direction, in a position threetimes the first space distant in the +X direction and three times thesecond space distant in the −Y direction, in a position the first spacedistant in the +X direction and three times the second space distant inthe +Y direction, in a position the first space distant in the +Xdirection and three times the second space distant in the −Y direction,in a position the first space distant in the −X direction and threetimes the second space distant in the +Y direction, in a position thefirst space distant in the −X direction and three times the second spacedistant in the −Y direction, in a position three times the first spacedistant in the −X direction and the second space distant in the +Ydirection, in a position three times the first space distant in the −Xdirection and three times the second space distant in the +Y direction,in a position three times the first space distant in the −X directionand the second space distant in the −Y direction, and in a positionthree times the first space distant in the −X direction and three timesthe second space distant in the −Y direction are added.

That is, the 16 fifth points 205 provided, respectively, with the firstpoint as a reference, in a position four times the first space distantin the +X direction, in a position four times the first space distant inthe +X direction and twice the second space distant in the +Y direction,in a position four times the first space distant in the +X direction andfour times the second space distant in the +Y direction, in a positionfour times the first space distant in the +X direction and twice thesecond space distant in the −Y direction, in a position four times thefirst space distant in the +X direction and four times the second spacedistant in the −Y direction, in a position twice the first space distantin the +X direction and four times the second space distant in the +Ydirection, in a position twice the first space distant in the +Xdirection and four times the second space distant in the −Y direction,in a position four times the second space distant in the +Y direction,in a position four times the second space distant in the −Y direction,in a position four times the first space distant in the −X direction, ina position four times the first space distant in the −X direction andtwice the second space distant in the +Y direction, in a position fourtimes the first space distant in the −X direction and four times thesecond space distant in the +Y direction, in a position four times thefirst space distant in the −X direction and twice the second spacedistant in the −Y direction, in a position four times the first spacedistant in the −X direction and four times the second space distant inthe −Y direction, in a position twice the first space distant in the −Xdirection and four times the second space distant in the +Y direction,and in a position twice the first space distant in the −X direction andfour times the second space distant in the −Y direction are added.

As shown in FIG. 47B, the constituent unit of the base pattern 200 maybe a unit surrounded by two patterns the distance of which is threetimes the first space with the first point 201 as a reference, extendingin the Y direction, and connecting the fourth points 204, and twopatterns the distance of which is three times the second space with thefirst point 201 as a reference, extending in the X direction, andconnecting the fourth points 204 in addition to the constituent unit ofFIG. 46E. Alternatively, the constituent unit of the base pattern 200may include a unit surrounded by two patterns the distance of which isfour times the first space with the first point 201 as a reference,extending in the Y direction, and connecting the fifth points 205, andtwo patterns the distance of which is four times the second space withthe first point 201 as a reference, extending in the X direction, andconnecting the fifth points 205.

As exemplarily described above, according to the embodiments, a wiringlayout by sidewall method in which the sidewall is formed three times isdesigned by using the base pattern 200 on which constituent units arearrayed two-dimensionally. Then, a pattern is formed by the sidewallmethod using one of the first point 201 and the pattern connecting thefourth points 204 as a mandrel.

As shown in FIG. 47C, by using the base pattern 200 on which suchconstituent units are arrayed two-dimensionally, a wiring layout by thesidewall method in which the sidewall is formed three times is designed.

Then, a pattern is formed by the sidewall method using one of the firstpoints 201 and the pattern connecting the fifth points 205 as a mandrel.In other words, it can be said that the first point 201, the patternconnecting the second points 202, the pattern connecting the thirdpoints 203, the pattern connecting the fourth points 204, and thepattern connecting the fifth points 205 are differentiated with eachother by five different colors.

Next, a case of the sidewall method in which the sidewall is formed ntimes is explained.

The constituent unit of the base pattern 200 will be first to(2^((n-1))+1)-th points. Here, n is a natural number not less thanunity. The (2^((n-1))+1)-th points will be surrounded by two patternsthe distance of which is (2^((n-1))+1) times the first space with thefirst point 201 as a reference, extending in the Y direction, andconnecting (2^((n-1))+1)-th points, and two patterns the distance ofwhich is (2^((n-1))+1) times the second space with the first point 201as a reference, extending in the X direction, and connecting the(2^((n-1))+1)-th points.

Then, a pattern is formed by the sidewall method using one of the firstpoint and the pattern connecting the (2^((n-1))+1)-th points.

FIG. 48 exemplarily shows a base pattern 200 used in the sidewall methodwhere sidewall is formed n times. As shown in FIG. 48, the base pattern200 includes first point 201 through (2^((n-1))+1)-th points 20 n. Inother words, it can be said that the first point 201, the patternconnecting the second points 202, and the pattern connecting the n-thpoints 20P are differentiated with each other by (2^((n-1))+1) differentcolors. So, the different colors P=(2^((n-1))+1), “n” is the sidewallmethod in which the sidewall is formed n times.

Next, the effect of the embodiment is explained.

It is possible to use the base pattern 200 in the embodiment as a basepattern of a wiring layout in the sidewall method in which the sidewallis formed n times.

Sixth Embodiment

Next, a design method of a wiring layout formed by the sidewall methodaccording to a sixth embodiment will be described.

FIG. 50 is a flow chart illustrating a design method of a wiring layoutand a method for manufacturing a semiconductor device according to asixth embodiment.

FIG. 51A is a plan view illustrating a sidewall wiring grid used in thedesign method of the wiring layout according to the sixth embodiment,and FIG. 51B shows an XY rectangular coordinate system adopted in FIG.51A.

As shown in FIG. 51A and step S1 of FIG. 50, first, the sidewall wiringgrid 600 is prepared. The sidewall wiring grid 600 is used for thewiring layout formed by the sidewall method.

As shown in FIG. 51B, in the embodiment, the XY rectangular coordinatesystem is adopted in order to describe the sidewall wiring grid 600. Inthe XY coordinate system, the upward direction in the figure is referredto as the +Y direction and the opposite direction is referred to as the−Y direction. The direction 90 degrees rotated clockwise from the +Ydirection is referred to as the +X direction and the opposite directionis referred to as the −X direction. The “+X direction” and the “−Xdirection” are together referred to also as the “X direction”. The “+Ydirection” and the “−Y direction” are together referred to also as the“Y direction”. In each of the drawings to be described later, the sameXY rectangular coordinate system is used according to the necessity.

The sidewall wiring grid 600 includes, for example, three kinds ofgrids, namely, a plurality of red grids R disposed in a matrixconfiguration, a plurality of blue grids B disposed in a matrixconfiguration and a plurality of colorless grids C.

The plurality of red grids R are disposed in a matrix configuration inthe X direction at a third period and in the Y direction at a fourthperiod. The plurality of blue grids B are disposed in a matrixconfiguration in the X direction at the third period and in the Ydirection at the fourth period. However, the blue grids B are disposedin the X direction with a shift of a half period of the third period andin the Y direction with a shift of a half period of the fourth period.

The plurality of colorless grids C are disposed one by one between thered grids R adjacent in the X direction and between the blue gridsadjacent in the X direction. Therefore, the plurality of colorless gridsC include grids disposed in a matrix configuration in the X direction atthe third period and in the Y direction at the fourth period, and gridsdisposed in a matrix configuration in the X direction at the thirdperiod and in the Y direction at the fourth period and disposed in the Xdirection with a shift of a half of the third period and in the Ydirection with a shift of a half of the fourth period

In the embodiment, the third period is taken as the same as the fourthperiod. The shape of the red grids R, the blue grids B and the colorlessgrids C is taken as a square having a length of one side being the samelength d as a half period of the third period and the fourth period.When the X direction of the sidewall wiring grid 600 is taken as a rowdirection and the Y direction is taken as a column direction, thesidewall wiring grid 600 is in a matrix configuration in which threekinds of grids are disposed in the column direction and the rowdirection.

An arbitrary grid R is taken as the grid R11 at the 1st row and the 1stcolumn. Starting from the grid R11, the grid R at the j-th row in the Xdirection and at the i-th column in the Y direction is taken as the gridRij. For example, the arrangement of the grids in the 1st row is inorder of the grid C12, the grid R13, the grid C14, the grid R15, thegrid C16, the grid R17, the grid C18 and the grid R19 from the grid R11in the +X direction. The arrangement of the grids in the second row isin order of the grid B22, the grid C23, the grid B24, the grid C25, thegrid B26, the grid C27, the grid B28 and the grid C29 from the grid C21adjacent to the grid R11 in the +Y direction along the +X direction. Thearrangement in the first column is in order of the grid C21, the gridR31, the grid C41, the grid R51, the grid C61 the grid R71, the grid C81and the grid R91 from the grid R11 in the +Y direction.

FIG. 52A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 52B showsan XY rectangular coordinate system adopted in FIG. 52A.

Next, as shown in step S2 of FIG. 50 and in FIG. 52A, grid wiring isperformed through connecting between the grids with a wiring. Whenconnecting between the grids with a wiring, following three connectionrules are applied. The first is that a start point of the wiring and anend point of the wiring are grids of the same color of red or blue. Thesecond is that a grid with color different from the color of the startpoint and the end point are not used as a pathway of the wiring.However, a colorless grid C can be used as a pathway of the wiringregardless of the color of the start point of the wiring and the endpoint of the wiring. Third is that a colorless grid C set to the pathwayof the wiring is set to a grid with the same color as the color of thegrid of the start point and the grid of the end point.

For example, first, the red grid R is selected as the grid SP1 of thestart point and the grid GP1 of the end point of the wiring. Forexample, the grid R75 is taken as the grid SP1 of the start point, andthe grid R35 is taken as the grid GP1 of the end point. Next, a wiringis disposed on the grid C76 between the grid SP1 and the grid R77adjacent to the grid SP1 in the +X direction, the grid R77 having thesame color as the grid SP1 of the start point, and the grid SP1 isconnected to the grid R77 by the wiring. Next, a wiring is disposed onthe grid C67 between the grid R77 and the grid R57 adjacent to the gridR77 in the −Y direction, the grid R57 having the same color as the gridR77, and the grid R77 is connected to the grid R57 by the wiring.

Next, a wiring is disposed on the grid C47 between the grid R57 and thegrid R37 adjacent to the grid R57 in the −Y direction, the grid R37having the same color as the grid R57, and the grid R57 is connected tothe grid R37 by the wiring. Furthermore, a wiring is disposed on thegrid C36 between the grid R37 and the grid GP1 of the end point adjacentto the grid R37 in the −X direction, the grid GP1 having the same coloras the grid R37, and the grid R37 is connected to grid GP1 of the endpoint by the wiring. In this manner, connection from the grid SP1 of thestart point to the grid GP1 of the end point is made by the wiring sothat the red grid R and the colorless grid C form a pathway of thewiring. This determines one pathway passing through only the red andcolorless grids.

The grid of the start point and the grid of the end point in the wiringmay not be limited to be set one by one. For example, the blue grid B84is selected as the grid SP2 of one start point. Two grids of the bluegrid B66 and the blue grid B28 are selected as the grid GP2 and the gridGP3 of the end points. Next, a wiring is disposed on the grid C74, thegrid C54, the grid C45 and the grid C56 so that the grid B64, the gridB44 and the grid B46 having the same color as the grid SP2 of the startpoint form a pathway of the wiring from the grid SP2 to the grid GP2,and adjacent grids B are connected.

Furthermore, a wiring is disposed on the grid C43, the grid C32, thegrid C23, the grid C25 and the grid C27 so that the grid B44, the gridB42, the grid B22, the grid B24 and the grid B26 having the same coloras the grid SP2 of the start point form a pathway of the wiring from thegrid SP2 to the grid GP3, and the adjacent grids B are connected.

In this manner, the wiring is caused to pass through the blue grids Band the colorless grids C, and connection is made from the grid SP2 ofone start point to the grid GP2 and the grid GP3 of two end points bythe wiring. This determines two pathways passing through only the blueand colorless grids. Thus, the wiring pattern connecting the grid SP ofthe start point to the grid GP of the end point is formed.

An one-line cutting pattern 42 or 36 a shown in FIGS. 8A and 9A may beallocated to the most outer circumferential grid in the sidewall wiringgrid 600, and thus it is preferable not to form the wiring patternthereon.

FIG. 53A is a plan view illustrating a mask pattern for trimming in thesixth embodiment, and FIG. 53B shows an XY rectangular coordinate systemadopted in FIG. 53A.

Next, as shown in step S3 of FIG. 50 and in FIG. 53A, the trimming maskpattern 601 is made after forming the wiring pattern. The trimming maskpattern 601 is a mask for removing unnecessary wirings in the laterprocess of the manufacturing process of the semiconductor device. In thecase where a half pitch of the wiring pattern is 30 nm, the trimmingmask is expanded with 15 nm in each of the X direction and the Ydirection with respect to the wiring pattern, and the margin is allowedfor dimension.

FIGS. 54A and 54B are process plan views illustrating a method forforming the trimming mask in the sixth embodiment.

Next, as shown in FIG. 54A, for example, a trimming mask pattern 601 ais formed expanding from the end edge of the wiring pattern with 50 nm.The wiring is not disposed on the grid C65, the grid R55, the grid C34and the grid R33, however the wiring is disposed on adjacent grids.Therefore, the expanded trimming mask pattern 601 a overlaps the gridC65, the grid R55, the grid C34 and the grid R33 and covers those grids.Consequently, there is no hole in the grid C65, the grid R55, the gridC34 and the grid R33, except for a portion where the trimming maskpattern 601 a may have an opening.

Subsequently, as shown in FIG. 54B, the end edge of the expandedtrimming mask pattern 601 a is shrunken with a width of 35 nm. Thisallows the trimming mask pattern 601 expanded with 15 nm in each of theX direction and the Y direction with respect to the wiring pattern to beformed. It prevents a hole unresolved in lithography being formed on thegrids where the wiring is not disposed in the trimming mask pattern 601.

FIG. 55A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 55B showsan XY rectangular coordinate system adopted in FIG. 55A.

Next, as shown in step S4 of FIG. 50 and in FIG. 55A, dummy wirings areallocated to the grids C with wiring not arranged.

First, a preferred direction of the dummy wiring allocated between theadjacent grids R or between the adjacent grids B, namely, whichdirection of the X direction or the Y direction is preferentiallyconnected is decided ahead of time. The grid C to which the dummy wiringcan be allocated is a grid contacting grids R or grids B, i.e. the gridsR contacting the grid C in the +X direction and −X direction, the gridsB contacting the grid C in the +X direction and −X direction, the gridsR contacting the grid C in the +Y direction and the −Y direction or thegrids B contacting the grid C in the +Y direction and the −Y direction,any of which the wiring is not connected to.

For example, the grid R73 and the grid R71 contacting the grid C72 inthe +X direction and −X direction, and the grid B82 and the grid B62contacting the grid C72 in the +Y direction and the −Y direction are notpathways of the wiring, i.e. have no wiring connected thereto.Therefore, the grid C72 can be disposed with the dummy wiring connectingthe grid R73 to the gird R71 in the X direction, and can be disposedwith the dummy wiring connecting the grid B82 to the grid B62 in the Ydirection. Therefore, when the preferred direction is a horizontaldirection, namely, the X direction, the dummy wiring connecting the gridR73 to the grid R71 in the X direction may be allocated.

With regard to the grid C87, the red grid R77 contacting the grid C87 inthe −Y direction is the pathway of the wiring, and thus the dummy wiringcannot be connected to the grid R77. Therefore, the dummy wiringconnecting the grid B86 to the grid B88 in the X direction is allocatedto the grid C87.

With regard to the grid C58, the grid R57 contacting the grid C58 in the−X direction is the pathway of the wiring, and thus the dummy wiringcannot be connected to the grid R57. Therefore, the dummy wiringconnecting the grid B48 to the grid B68 in the Y direction is allocatedto the grid C58.

Since with regard to the grid C85, the grid C65, the grid C34 and thegrid C38, the grid R or the grid B contacting the grid C in one of the+X direction and the −X direction, and the grid R or the grid Bcontacting the grid C in one of the +Y direction and the −Y directionare pathways of the wiring, the dummy wiring cannot be allocated. Inthis case, a blank grid C0 is allocated. The blank grid C0 is held to beblank.

FIG. 56A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment shown as S4 of FIG.50, and FIG. 56B shows an XY rectangular coordinate system adopted inFIG. 56A.

As shown in FIG. 56A, the dummy wiring is disposed on the grid Cpossible to be allocated. The dummy wiring connecting the adjacent gridsR in the X direction is disposed on the grid C12, the grid C14, the gridC16, the grid C18, the grid C92, the grid C94, the grid C96 and the gridC98 in the outermost circumference of the sidewall wiring grid 600, andthe dummy wiring connecting the adjacent grids R in the Y direction isdisposed on the grid C21, the grid C41, the grid C61, the grid C81, thegrid C29, the grid C49, the grid C69 and the grid C89. The dummy wiringconnecting the adjacent girds R in the X direction is disposed on thegrid C52. The dummy wiring connecting the adjacent grids B in the Xdirection is disposed on the grid C87. The dummy wiring connecting theadjacent grids B in the Y direction is disposed on the grid C58 and thegrid C78. The dummy wiring connecting the adjacent grids R in the Xdirection according to the preferred direction is disposed on the gridC72 to which any dummy wiring can be allocated. The grid B62 and thegrid B 82 are isolated grids RBI.

FIGS. 57A to 57C are plan views illustrating a method for determining apreferred direction of a dummy wiring, and FIG. 57D shows an XYrectangular coordinate system adopted in FIGS. 57A to 57C.

As shown in FIG. 57A, for example, in the case where a rectangularwiring pattern having four corners of the grid R11, the grid R19, thegrid R51 and the grid R59 is formed, perpendicular preference, namely,the dummy wiring connecting in the Y direction is assumed to bepreferentially allocated.

In this case, as shown in FIG. 57B, the dummy wiring connecting theadjacent grid B24 and the grid B44 in the Y direction and the dummywiring connecting the grid B26 and the grid B46 in the Y direction areallocated on the grid C34 and the grid C36. However, in this case, thegrid R33, the grid R35 and the grid R37 are isolated from the othergrids (hereinafter it may be simply referred to as “isolated grid”). Inthe lithography and patterning in the manufacturing process of thesemiconductor device, it is difficult to form a wiring corresponding toan isolated grid. Then, it is discussed whether change of the connectiondirection of the dummy wiring is possible or not. In FIG. 57B, the dummywirings around the isolated grids R33, R35 and R37 are taken ascandidates for the change. The connection direction of the candidatedummy wirings is changed and horizontal preference, namely, the dummywiring connecting in the X direction is allocated.

As shown in FIG. 57C, the dummy wiring connecting the adjacent grids Rin the X direction is disposed on the grid C34 and the grid C36. Thiscan reduce the number of the isolated grids.

As shown in step S5 of FIG. 50, in FIG. 56A described above, change ofconnection direction of the dummy wiring shorter than a prescribedlength or the dummy wiring around the isolated red/blue grids will betried. It is because of difficulty of forming a wiring corresponding toa dummy wiring shorter than a prescribed length in the lithography orpatterning in the manufacturing process of the semiconductor device. Thechange of the connection direction will be tried in order of a lengthfrom a tip end of the dummy wiring pattern to a bend portion of thedummy wiring pattern. For example, the prescribed length is taken as 4grids. The grid B48 is at the tip end of the dummy wiring pattern, and alength to the grid B88 at the bend portion of the dummy wiring is alength of 4 grids. Then, the change of the connection direction of thedummy wiring disposed on the grid C58 and the grid C78 between the gridB48 and the grid B88 will be tried. However, since the grid R57 and thegrid R77 contacting the grid C58 and the grid C78 in the −X directionare set to the pathway of the wiring, the dummy wiring cannot beconnected. Thus, the connection direction of the dummy wiring disposedon the grid C58 and the grid C78 cannot be changed.

Next, for example, the prescribed length is taken as 2 grids. The gridB86 is at the tip end of the dummy wiring pattern, and a length to thegrid B88 at the bend portion of the dummy wiring is a length of 2 grids.Then, the change of the connection direction of the dummy wiringarranged on the grid C78 between the grid B86 and the grid B88 will betried. However, since the grid R77 contacting the grid C87 in the −Ydirection is set to the pathway of the wiring, the dummy wiring cannotbe connected. Thus, the connection direction of the dummy wiringdisposed on the grid C87 cannot be changed.

Next, for example the isolated grid will be discussed. The grid B62 andthe grid B82 are at the tip end of the dummy wiring pattern, and areisolated grids. Then, the change of the connection direction of thedummy wiring disposed on the grid C around the grid B62 and the grid B82will be tried. The connection direction of the dummy wiring of the gridC72 can be changed to the Y direction. So the dummy wiring of grid C72is not the pathway of the wiring.

FIG. 58A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 58B showsan XY rectangular coordinate system adopted in FIG. 58A.

As shown in FIG. 58A, the connection direction of the dummy wiring ofthe grid C72 can be changed to the Y direction. This can reduce thenumber of isolated grids.

FIG. 59A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the sixth embodiment, and FIG. 59B showsan XY rectangular coordinate system adopted in FIG. 59A.

As shown in step S6 of FIG. 50 and in FIG. 59A, a mandrel is selected.For example, the grid R, the wiring connected to the grids R and thedummy wiring are selected as the mandrel. Next, the one-line cuttingpattern is allocated to the blank grid C0. The color of the one-linecutting pattern is a color of the selected mandrel. It is for preventingconnection of the wiring to the dummy wiring. The one-line cuttingpattern may be one kind of pattern with a thin slit as shown in FIG.59A.

In this manner, the layout of the wiring can be designed using thesidewall method wiring grid.

According to the design method of the wiring layout of the embodiment,the wiring layout including the wiring pattern connecting the grid SP ofthe start point to the grid GP of the end point can be designed. In bothof the wiring pattern including the pathway passing through only the redand colorless grids, and the wiring pattern including the pathwaypassing through only the blue and colorless grids, the wiring layoutincluding the pattern forming the separated wiring can be designed.Hereinafter, the above may be simply referred to as “separated wiring”.

Furthermore, since the wiring pattern including the pathway passingthrough only the red and colorless grids and the wiring patternincluding the pathway passing through only the blue and colorless gridsare divided each other, one of the wiring pattern including the pathwaypassing through only the red and colorless grids and the wiring patternincluding the pathway passing through only the blue and colorless gridscan be the pattern of the mandrel of the wiring layout formed by thesidewall method. Thus, in the wiring layout formed by the sidewallmethod, free design including the separated wiring becomes possible, andhighly integrating the wiring layout can be achieved.

According to the embodiment, difficult patters for forming in thelithography and the patterning can be reduced by changing the connectiondirection of the dummy wiring.

FIG. 60A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid before changing a connection direction ofthe dummy wiring, and FIG. 60B a plan view illustrating a state in whicha wiring is drawn on the sidewall wiring grid after changing aconnection direction of the dummy wiring.

As shown in FIG. 60A, before the change of the connection direction ofthe dummy wiring, isolated grids RBI are arranged.

As shown in FIG. 60B, as a result of the change of the connectiondirection in order of a length from a tip end of the dummy wiringpattern to a bend portion of the dummy wiring pattern, the number of theisolated grids RBI can be reduced.

For example, the number of portions including the isolated grids, whereformation is difficult in the lithography and the patterning, can bereduced by the change of the connection direction. For example, when thegrid R and the wiring connected to the grids R are selected as themandrel, the number of the isolated grids RBI can be reduced from 35 to12. For another example, when the grid B and the wiring connected to thegrids B are selected as the mandrel, the number of isolated grids RBIcan be reduced from 20 to 18.

The wiring has been drawn by disposing the wiring manually between thegrid of the start point and the grid of the end point, however thedisposal is not limited thereto. For example, information about the gridof the start point and the grid of the end point is given as a netlist,and an automatic wiring algorithm represented by a maze method isapplied so as to pass through only grid of the same color or colorless,and thus the wiring pathway may be automatically determined.

Next, a program supporting the design of the wiring layout formed by thesidewall method will be described.

The program according to the embodiment causes the computer to performthe following procedure.

First, the procedure is performed displaying the sidewall wiring grid600 on a display device, namely, the display shown as FIG. 49, forexample. As shown in FIG. 50A, the sidewall wiring grid 600 is providedwith three kinds of grids including the plurality of red grids R and theplurality of blue grids disposed in a matrix configuration, and theplurality of colorless grids C. The computer preferably color-codes thered grids and the blue grids with different colors or hatchesdifferently on the display device so as to lay out easily for adesigner.

Next, the designer selects the grid SP of the start point and the gridGP of the end point of the wiring, for example, by a drag operation of amouse via an input device on the sidewall wiring grid 600 displayed onthe display device. At this time, the computer performs the proceduredisplaying the selected grid SP of the start point and the selected gridGP of the end point.

Next, the designer disposes the wiring according to a connection rulefrom the grid S to the grid G via the display device on the sidewallwiring grid 600 displayed on the display device. At this time, thecomputer performs the procedure connecting the adjacent grids with thedisposed wiring.

Next, the designer specifies a range of the wiring pattern via the inputdevice. At this time, the computer performs the procedure displaying atrimming mask pattern 601 covering the specified wiring pattern. Whenthe designer instructs to store the trimming mask pattern 601 via theinput device, the computer performs the procedure storing the trimmingmask pattern 601 displayed on the display device. Furthermore, when thedesigner instructs to clear the trimming mask pattern 601 from thedisplay via the input device, the computer performs the procedureerasing the trimming mask pattern 601 displayed on the display device.

Next, the designer specifies the preferred direction of the dummy wiringdisposed on the grid C having no wiring disposed on the sidewall wiringgrid 600 displayed on the display device via the input device. At thistime, the computer performs the procedure in which the dummy wiring withthe preferred direction being preferred is disposed on the grid C wherethe dummy wiring can be allocated. The computer performs the procedurein which the grid C where the dummy wiring cannot be allocated isreplaced with the blank grid C0.

Next, the designer specifies a prescribed length of the dummy wiringhaving the connection direction to be changed via the input device. Atthis time, the computer performs the procedure displaying the dummywiring with a length shorter than the prescribed length or the dummywiring around the isolated red/blue grids as a candidate for the change.

The designer instructs to change the connection direction of the dummywiring of the candidate via the input device. At this time, the computerperforms the procedure changing the connection direction of the dummywiring of the candidate of the change to display the change.

Next, the designer selects the mandrel via the input device. At thistime, the computer color-codes the red grid R or the blue grid Bselected for the mandrel with different colors, and hatches differentlyso as to be easy for the designer to lay out on the sidewall wiring grid600. The computer performs the procedure allocating the one-cuttingpattern to the blank grid C0.

As a result, the wiring pattern including the pathway passing throughonly the red and colorless grids and the wiring pattern including thepathway passing through only the blue and colorless grids are patternsseparated each other.

In this way, the program assisting the design of the wiring layoutformed by the sidewall method allows the computer to perform to assistthe design of the wiring layout as shown in FIG. 59A.

According to the program of the embodiment, it is possible to cause thecomputer to assist the design of the wiring layout, and thus a timeneeded for the design of the wiring layout formable by the sidewallmethod can be reduced. After the designer disposed a plurality ofwirings and dummy wirings, the computer may perform the procedure inwhich the program replaces the pattern collectively by clicking aconversion button displayed in the display device. As a result, sincethe designer can arrange other parts in a state where each part isdisplayed, the layout is easy to be made.

Next, a method for manufacturing a semiconductor device including thewiring formed based on the wiring layout by the sidewall method isexplained.

FIG. 61A is a mask pattern using a method for manufacturing asemiconductor device according to the sixth embodiment, and FIG. 61Bshows an XY rectangular coordinate system adopted in FIG. 61A.

FIGS. 62A to 62C are process plan views illustrating the method formanufacturing the semiconductor device according to the sixthembodiment.

First, as shown in step S7 of FIG. 50, FIG. 61A, and FIG. 62A, in thelayout of the wiring described above, for example, a mandrel 602 isformed on an insulating film 603, as the grid R selected for the mandrel602, the wiring connected to the grid R, and the dummy wiring being apattern of the mandrel 602. A width of the mandrel 602 is set to, forexample, d. At this time, the mandrel patterns shown in FIGS. 6 to 9 orFIGS. 24 to 39 are adopt by the mask pattern shown as FIG. 61A.

Next, as shown in FIG. 62B, the mandrel 602 is subjected to slimming asnecessary, and the width is set to d/2. At this time, a space betweenthe mandrels 602 is set to 3d/2 being three times of the width d/2 ofthe mandrel 602.

Next, as shown in FIG. 62C, a sidewall 604 is formed so as to cover themandrel 602. A thickness of the sidewall 604 is controlled to be d/2.

FIG. 63A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, and FIG. 63B shows an XY rectangular coordinate systemadopted in FIG. 63A.

FIGS. 64A to 64C are process sectional views illustrating the method formanufacturing the semiconductor device according to the sixthembodiment.

Next, as shown in FIG. 63A and FIG. 64A, the sidewall 604 is subjectedto etching back and an upper surface of the mandrel 602 is exposed.

Next, as shown in FIG. 64B, the mandrel 602 is removed by etching.Thereby, the sidewalls 604 with the width of d/2 are disposed with aspace of d/2 on an insulating film 603.

As shown in FIG. 64C, the insulating film 603 is etched using thesidewall 604 as a mask, and thereby the insulating film 603 isselectively etched and a concave portion 605 is formed. After that, thesidewall 604 is removed. Thereby, the concave portions 605 with a widthof d/2 are disposed with a space of d/2 on an upper surface of theinsulating film 603.

FIG. 65A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, FIG. 65B shows an XY rectangular coordinate system adoptedin FIG. 63A, and FIG. 65C is a process sectional view illustrating themethod for manufacturing the semiconductor device according to the sixthembodiment.

Next, as shown in FIGS. 65A and 65C, a conductive material is depositedon the insulating film 603 so as to fill in the concave portion 605. Theconductive material is planarized until the upper surface of theinsulating film 603 is exposed. Thereby, wirings 606 with a width of d/2are disposed with a space of d/2 on the upper surface of the insulatingfilm 603. In this way, the wiring 606 buried in the concave portion 605is formed by forming a pattern by a sidewall processing.

FIG. 66A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, and FIG. 66B shows an XY rectangular coordinate systemadopted in FIG. 66A.

As shown in step S8 of FIG. 50 and in FIG. 66A, a trimming mask 607 isarranged on the insulating film 603 based on the trimming mask pattern601.

FIG. 67A is a process plan view illustrating the method formanufacturing the semiconductor device according to the sixthembodiment, and FIG. 67B shows an XY rectangular coordinate systemadopted in FIG. 67A.

Next, as shown in FIG. 67A, unnecessary wiring patterns are removed byetching the insulating film 603 and the wiring 606 using the trimmingmask 607 as a mask. In this way, a semiconductor device 6 ismanufactured.

According to the method for manufacturing the semiconductor device ofthe embodiment, a length of a space between the adjacent wirings 40 in adirection perpendicular to an extending direction of the wiring 40buried in the concave portion 605 can be smaller than a length of thesmallest space of a pattern resolvable by a lithography method.Therefore, since the free design including the wiring space smaller thanthe minimum value of the space resolved by the lithography becomespossible, the semiconductor device including the highly integratedwiring can be manufactured.

In particular, the design of the wiring is possible with a focus on thefinal layout instead of designing the wiring by calculating the sidewallfrom the mandrel. As a result, design efficiency is markedly improved.

Next, the semiconductor device 6 according to the embodiment isdescribed.

As shown in FIG. 67A, the semiconductor device 6 is provided with aplurality of wirings 606 a connecting the grids R in the X direction, aplurality of wirings 606 b connecting the grids R in the Y direction, aplurality of wirings 606 c connecting grids B in the X direction, and aplurality of wirings 606 d connecting the grids B in the Y direction.

When a plurality of first lines extending in the Y direction anddisposed with ½ period of the third period in the X direction aresupposed in the XY plane and integer numbers are allocated to the firstlines in order from the end, and when a plurality of second linesextending in the X direction, disposed with ½ period of the fourthperiod in the Y direction, and intersecting the first lines are supposedin the XY plane and integer numbers are allocated to the second lines inorder from the end, the wirings 606 a are disposed in the odd-numberedfirst lines and the wirings 606 b are disposed in the even-numberedfirst lines. Further, the wirings 606 b are disposed in the odd-numberedsecond lines and the wirings 606 a are disposed in the even-numberedsecond lines.

Then, at least one of the wirings 606 a connects with the wiring 606 band at least one of the wirings 606 c connects with the wiring 606 d.Further, the wiring 606 a and the wiring 606 b, and the wiring 606 c andthe wiring 606 d are separated from each other.

The semiconductor device 6 according to the embodiment includes thewiring space narrower than the minimum value of space by the resolutionof lithography, and therefore, the degree of integration is high.

Seventh Embodiment

Next, a seventh embodiment will be described.

First, a design method of a wiring layout formed by the two-timesidewall method according to the seventh embodiment will be described.

FIG. 68A is a plan view illustrating a sidewall wiring grid used in adesign method of a wiring layout according to a seventh embodiment, andFIG. 68B shows an XY rectangular coordinate system adopted in FIG. 68A.

As shown in step S1 of FIG. 50 and in FIG. 68A, first, a sidewall wiringgrid 700 is prepared. The sidewall wiring grid 700 is used for a wiringlayout formed by the sidewall method.

As shown in FIG. 68B, also in the embodiment, the XY rectangularcoordinate system similar to the above is adopted in order to describethe sidewall wiring grid 700.

The sidewall wiring grid 700 includes, for example, six kinds of grids,namely, a plurality of red grids R disposed in a matrix configuration, aplurality of blue grids B disposed in a matrix configuration, aplurality of green grids G disposed in a matrix configuration, aplurality of colorless grids C, a plurality of colorless grids M and aplurality of colorless grids N.

The plurality of red grids R are disposed in a matrix configuration witha fifth period in the X direction and with a sixth period in the Ydirection. The plurality of blue grids B are disposed in a matrixconfiguration with a fifth period in the X direction and with a sixthperiod in the Y direction. However, the blue grids B are disposed with ashift of a half period of the fifth period in the X direction and with ashift of a half period of the sixth period in the Y direction.

The plurality of green grids G are disposed in a matrix configurationwith a half period of the fifth period in the X direction and with ahalf period of the sixth period in the Y direction. However, the greengrids G are disposed with a shift of ¼ period of the fifth period in theX direction and with a shift of ¼ period of the sixth period in the Ydirection.

The plurality of colorless grids C are disposed one by one in a midwaybetween the adjacent red grids R in the X direction and in a midwaybetween the adjacent blue grids B in the X direction. Therefore, theplurality of colorless grids C include grids disposed in a matrixconfiguration with the fifth period in the X direction and with thesixth period in the Y direction and grids disposed with a shift of thehalf of the fifth period in the X direction and with a shift of the halfperiod of the sixth period in the Y direction.

The plurality of colorless grids M are disposed one by one between thegrid B and the grid C. The plurality of colorless grids N are disposedone by one between the grid R and the grid C.

In the embodiment, the fifth period is taken as the same as the sixthperiod. Shapes of the red grid R, the blue grid B, the green grid G, thecolorless grid C, the colorless grid M and the colorless grid N aretaken as a square with one side of a length d2 equal to ¼ period of thefifth period and the sixth period. When the X direction of the sidewallwiring grid 700 is taken as a row direction and the Y direction is takenas a column direction, the sidewall wiring grid 700 is in a matrixconfiguration in which six kinds of grids are disposed in the rowdirection and the column direction.

An arbitrary grid R is taken as the grid R0101 at the 1st row and the1st column, namely, at the 01st row and the 01st column. Starting fromthe grid R0101, the grid R at the j-th column in the X direction and atthe i-th row in the Y direction is taken as the grid Rij. For example,the arrangement of the grids in the first row is in order of the gridN0102, the grid C0103, the grid N0104, the grid R0105, the grid N0106,the grid C0107, the grid N0108, the gird R0109, the grid N0110, the gridC0111, the grid N0112, the grid R0113, the grid N0114, the grid C0115,the grid N0116, the grid R0117, the grid N0118, the grid C0119, the gridN0120 and the grid R0121 from the grid R0101 in the +X direction.

FIG. 69A is a plan view illustrating a state in which a wiring is drawnon the sidewall wiring grid in the seventh embodiment, and FIG. 69Bshows an XY rectangular coordinate system adopted in FIG. 69A.

As shown in step S2 of FIG. 50 and in FIG. 69A, grid wiring is performedthrough connecting between the grids with a wiring. When connectingbetween the grids with a wiring, following four connection rules areapplied in addition to the three connection rules in the sixthembodiment described above.

The first is that a wiring connecting between the red grids R or awiring connecting between the blue grids B can be disposed on the gridC. The second is that a wiring connecting between the blue grids B or awiring connecting between the green grids G can be disposed on the gridM.

The third is that a wiring connecting between the red grids R or awiring connecting between the green grids G can be disposed on the gridN. The fourth is when a wiring having the green grid G as a pathway isbent, the wiring can be bent so as to come around the red grid R or theblue grid B being inside the wiring, and cannot be bent so as to comearound the grid C being inside the wiring.

For example, a wiring is disposed between the grid B1919 taken as thegrid SP1 of the start point and the grid B1507 taken as the grid GP1 ofthe end point via the grid B1915, the grid 81911 and the grid B1511, andthen the grid SP1 of the start point becomes continuous with the grid GP1 of the end point. Furthermore, a wiring is disposed between the gridB1511 and the grid B0307 taken as the grid GP2 of the end point via thegrid B1515, the grid B1519, the grid B1119, the grid B1115, the grid80715, the grid B0711 and the grid B0311, and then the grid SP1 of thestart point becomes continuous with the grid GP2 of the end point.

Similarly, a wiring is disposed between the grid R1709 taken as the gridSP2 of the start point and the grid R0509 taken as the grid GP3 of theend point via the grid R1705, the grid R1305, the grid R0905 and thegrid R0505, and then the grid SP2 of the start point becomes continuouswith the grid GP3 of the end point. Furthermore, a wiring is disposedbetween the grid R1305 and the grid R1309 taken as the grid GP4 of theend point, and then the grid SP2 of the start point becomes continuouswith the grid GP4 of the end point.

Furthermore, a wiring is disposed between the grid G1816 taken as thegrid SP3 of the start point and the grid G1402 taken as the grid GP5 ofthe end point via the grid G1820, the grid G2020 and the grid G2002, andthen the grid SP3 of the start point becomes continuous with the gridGP5 of the end point.

Similarly, a wiring is disposed between the grid G1004 taken as the gridSP4 of the start point and the grid G1210 taken as the grid GP6 of theend point via the grid G0404, the grid G0410, the grid G0610, the gridG0606 and the gird G1206, and then the grid SP4 of the start pointbecomes continuous with the grid GP6 of the end point.

A wiring is disposed between the grid G1418 taken as the grid SP5 of thestart point and the grid G0808 taken as the grid GP7 of the end pointvia the grid G1412, the grid G1012 and the grid G1008, and then the gridSP5 of the start point becomes continuous with the grid GP7 of the endpoint.

A wiring is disposed between the grid G1420 taken as the grid SP6 of thestart point and the grid G0616 taken as the GP8 of the end point via thegrid G1020 and the grid G1016, and then the grid SP6 of the start pointbecomes continuous with the grid GP8 of the end point.

A wiring is disposed between the grid G0820 taken as the grid SP7 of thestart point and the grid G0214 taken as the grid GP9 of the end pointvia the grid G0220, and then the grid SP7 of the start point becomescontinuous with the grid GP9 of the end point. When needed, a trimmingmask pattern is formed similar to the sixth embodiment described above.

Next, using a method similar to the sixth embodiment described above,first, a pattern of the dummy wiring connecting the red grids R and theblue grids B is disposed. The dummy wiring connecting the adjacent redgrids R is disposed on one grid C and two grids N. The dummy wiringconnecting the adjacent blue grids is disposed on one grid C and twogrids M.

Next, a mandrel is selected. For example, the grid B, the wiringconnected to the grid B and the dummy wiring are selected for themandrel. Next, one-cutting pattern is allocated to the blank grid C0(the grid C0305, the grid C1909, the grid C1311). The allocatedone-cutting pattern has a color of the selected mandrel.

The dummy wiring connecting between the green grids G is disposed on thegrid M and the grid N capable of being allocated. The dummy wiring isallocated to the green grid M0314, grid M1815 as well, on which thedummy wiring cannot be allocated according to the rule that the dummywiring is allocated between the red grids R and between the blue gridsB. Different from the case of the dummy wiring allocated between the redgrids R and between the blue grids B, one-cutting pattern cannot beallocated to the dummy wiring disposed between the green grids G.

For example, the dummy wiring between grids G may also be cut by themethod shown in FIG. 70A to FIG. 75B. FIG. 70A to FIG. 75D are schematicviews showing the process of the two-time sidewall method. FIG. 70A is aplan view showing the upper face of an underlying layer 701. FIG. 70B isa cross-sectional view along the A-A line shown in FIG. 70A. The sameapplies from FIG. 71A to FIG. 75B.

As shown in FIG. 70A and FIG. 70B, a mandrel 703 is formed on theunderlying layer 701. The width of the mandrel 703 is the width d of thewiring pattern, and the space between neighboring mandrels 703 is alsomade to be d. Subsequently, the mandrel 703 is slimmed so that the linewidth thereof is d/2.

Next, as shown in FIG. 71A and FIG. 71B, a sidewall (sidewall film 705in which etching rate differs from mandrel 703) is formed on a side faceof the mandrel 703. The sidewall film 705 is formed, for example, sothat the width thereof is d/2. Consequently, a space of a width of d/2is formed between neighboring mandrels 703 including the sidewalls.

Next, as shown in FIG. 72A and FIG. 72B, the mandrel 703 is selectivelyremoved, and the sidewall film 705 is slimed to be the line width ofd/4. Subsequently, using the sidewall film 705 as a new mandrel, asidewall (an sidewall film 707 in which etching rate differs fromsidewall 705) is formed on the side face thereof. The sidewall film 707is formed so that the line width thereof is d/4. Consequently, a spaceof a width of d/4 is formed between neighboring mandrels (sidewall films705) including the sidewalls.

Next, as shown in FIG. 73A and FIG. 73B, the dummy wiring part betweengrids G is covered, for example, with a resist 709. Then, the sidewallfilm 705 that is a mandrel is removed. Since the dummy wiring part iscovered with the resist 709, the sidewall film 705 is not removed in thepart. Consequently, a wiring space of a width d/4 surrounded by thesidewall film 707 is formed on the underlying layer 701.

Subsequently, as shown in FIG. 74A and FIG. 74B, the underlying layer701 is etched using the sidewall film 707 as a mask, so as to form awiring trench 713. As shown in FIG. 74A, no wiring trench is formed inthe part where the sidewall film 705 is left.

Next, as shown in FIG. 75A and FIG. 75B, a wiring material is embeddedinto the wiring trench to form a wiring 715. As the result, as shown inFIG. 75A, no wiring 715 is formed in the dummy wiring part, and thewiring between grids G can be cut.

Alternatively, wirings corresponding to these grids G may be cut laterby electron beam or laser or the like from the outside. It may also bepossible to cut unnecessary pattern using a trimming mask, which isformed by using an apparatus that is able to expose a fine pattern withEUV (extreme ultraviolet).

In this manner, the layout of the wiring can be designed using wiringgrid according to the sidewall method.

According to the design method of the wiring layout of the embodiment,the wiring layout can be designed including the wiring patternconnecting the grid SP of the start point with the grid GP of the endpoint. The wiring layout can be designed including the pattern formingthe separated wiring, where the wiring pattern includes the pathwaypassing through only the red and colorless grids; the wiring patternincludes the pathway passing through only the blue and colorless grids;and the wiring pattern includes the pathway passing through only thegreen and colorless grids.

Furthermore, the wiring pattern including the pathway passing throughonly the red and colorless grids, the wiring pattern including thepathway passing through only the blue and colorless grids and the wiringpattern including the pathway passing through only the green andcolorless grids are divided one another. One of the wiring patternincluding the pathway passing through only the red and colorless gridsand the wiring pattern including the pathway passing through only theblue and colorless grids can be the pattern of the mandrel of the wiringlayout formed by the two-time sidewall method in which the sidewall isformed two times. Thus, free design including the separated wiringbecomes possible, and highly integrating the wiring layout can beachieved in the wiring layout formed by the sidewall method.

In the embodiment, when the wiring is disposed between the red grids Rand the blue grids B, the wiring is also disposed between the greengrids G, however the disposal is not limited thereto.

For example, first, a wiring is disposed between the red grids R and theblue grids B. After that, a dummy wiring is disposed between the redgrids R and the blue grids B. Next, a mandrel is selected, andone-cutting pattern is disposed on the pattern selected as the mandrel.A wiring and a dummy wiring may be disposed between the green grids G.Also in this case, the wiring connecting between the green grids G isformed in a loop. Therefore, the whole pattern in a loop is used as thewiring, alternatively unnecessary portions are cut by a trimming mask.

Next, a design method of a wiring layout formed by the two-time sidewallmethod will be described.

The program according to the embodiment causes the computer to performthe procedure shown in the following.

First, the computer may perform the procedure displaying the sidewallwiring grid 700 on the display device, for example. The wiring grid 700displayed includes, as shown in FIG. 68A, six kinds grids, namely, aplurality of red grids R disposed in a matrix configuration, a pluralityof blue grids B disposed in a matrix configuration, a plurality of greengrids G disposed in a matrix configuration, a plurality of colorlessgrids C, a plurality of colorless grids M and a plurality of colorlessgrids N.

Next, the designer selects the grid SP of the start point and the gridGP of the end point on the sidewall wiring grid 700 displayed in thedisplay device by using the input device, for example, a mouse dragginga pointer thereto. At this time, the computer performs the proceduredisplaying the selected grid SP of the start point and the grid GP ofthe end point.

Next, the designer disposes a wiring from the grid SP to the grid GPaccording to the connection rule via the input device on the sidewallwiring grid 700 displayed in the display. At this time, the computerperforms the procedure connecting between the adjacent grids by thedisposed wiring.

Next, the designer specifies the preferred direction of the dummy wiringdisposed on the grid C, the grid M and the grid N having no wiringdisposed on the sidewall wiring grid 700 displayed on the display devicevia the input device. At this time, the computer performs the procedurein which the dummy wiring connecting is disposed between the red andblue grids on the grid C, the grid M and the grid N, where the dummywiring can be allocated, with the preferred direction. The computerperforms the procedure replacing the grid C with the blank grid C0,where the dummy wiring cannot be allocated on the grid C.

Next, the designer specifies a prescribed length identifying the dummywiring having the connection direction to be changed via the inputdevice. At this time, the computer performs the procedure displaying thedummy wiring with a length shorter than the prescribed length. The dummywiring around the isolated grids are also displayed as a candidate forthe change.

The designer instructs to change the connection direction of the dummywiring of the candidate via the input device. At this time, the computerperforms the procedures changing the connection direction of the dummywiring, which is identified as the candidate to be changed, anddisplaying a result of the change.

Next, the designer selects the mandrel via the input device. At thistime, the computer color-codes the red grid R or the blue grid Bselected for the mandrel with different colors, and hatches differentlyso as to be easy for the designer to lay out on the sidewall wiring grid700. The computer performs the procedure allocating the one-cuttingpattern to the blank grid C0.

Next, the designer disposes the dummy wiring connecting between thegreen grids using the input device. At this time, the computer performsthe procedure in which the dummy wiring connecting between the greengrids is disposed on the grid M and the grid N on which the dummy wiringcan be allocated.

As a result, the wiring pattern including the pathway passing throughonly the red and colorless grids and the wiring pattern including thepathway passing through only the blue and colorless grids, and thewiring pattern including the pathway passing through only the red andcolorless grids are patterns separated one another.

In this way, the program assisting the design of the wiring layoutformed by the sidewall method allows the computer to assist the designof the wiring layout as shown in FIG. 69A.

According to the program of the embodiment, it is possible to cause thecomputer to assist the design of the wiring layout, and thus a timeneeded for the design of the wiring layout formable by the two-timesidewall method can be reduced.

The semiconductor device including the wiring formed based on the wiringlayout by the sidewall method forming the sidewall two times and themethod for manufacturing the same are the same as those in FIGS. 23A to23H shown in the third embodiment described above, and thus thedescription will be omitted.

Variation of the Seventh Embodiment

Next, a variation of the seventh embodiment will be described.

FIG. 76A is a plan view illustrating a state in which a wiring is drawnon a sidewall wiring grid in a variation of the seventh embodiment, andFIG. 76B shows an XY rectangular coordinate system adopted in FIG. 76A.

As shown in FIG. 76A, in the embodiment, the wiring disposed between thegreen grids is not cut using means of the electron beam or the like.Since the wiring disposed between the green grids is formed in a loop,the whole structure regards as a loop wiring. For example, the loopwiring is used as the grand line or the voltage source line. Theconfiguration and the effect other than the above of the embodiment arethe same as those of the seventh embodiment described above.

Eighth Embodiment

FIG. 77 is a flow chart showing a method of mask design according to aneighth embodiment. The designer designs a mask layout, for example,using the input unit, the computer and the display unit shown in FIG.49. That is, the designer operates the input unit to input designinformation into the controller in the computer. According to theinputted information, the controller, for example, draws (displays) apattern on the screen of the display unit.

As shown in FIG. 77, on the basis of the inputted design information,the controller draws an initial first wiring on a plane, for example, onthe screen of the display unit (S01). The first wiring, for example,connects two points set on the plane. The controller sets a firstforbidden region adjacent to the first wiring, where a subsequent firstwiring can not be drawn.

Subsequently, a counter “k” is set to be “1” and a following wiring isdrawn (S02). On the basis of the design information, the controllerdetermines, for example, whether a wiring to be drawn next is the firstwiring or a second wiring.

When the kind of wiring to be drawn next is the first wiring, a firstwiring is drawn connecting two points different from the two points forthe initial first wiring. The first wiring to be newly drawn can notpass through the first forbidden region set on the plane. The controllersets the first forbidden region adjacent to the first wiring newlydrawn.

On the other hand, when the kind of wiring to be drawn next is thesecond wiring, the controller draws a second wiring connecting twopoints different from the two points for the initial first wiring. Thesecond wiring can pass through the first forbidden region, but does notintersect the first wiring and is drawn spaced from the first wiring.The controller sets a second forbidden region adjacent to the secondwiring. The second forbidden region is a region where a subsequentsecond wiring can not be drawn.

Furthermore, a third forbidden region is set in a region where the firstforbidden region and the second forbidden region overlap each other(S03). Both the first wiring and the second wiring can not be drawn inthe third forbidden region.

Next, the controller determines whether or not the number of drawnwirings (the counter “k”) is equal to the total number of wirings “n”specified in the design information. When the number “k” of drawnwirings is equal to the total number of wirings “n,” the process movesto the subsequent step S05. On the other hand, when the number of drawnwirings “k” is not equal to the total number of drawn wirings “n,” “1”is added to the counter “k” and a wiring connecting new two points isdrawn (S02).

When the drawing of the first wiring and the second wiring is completed,the controller draws a third wiring in the second forbidden region(S05). In addition, the controller draws a fourth wiring in the firstforbidden region (S06).

Next, one of the third wiring and the fourth wiring is expanded into avacant space on the plane excluding the region where the first wiring isdrawn, the region where the second wiring is drawn, the first forbiddenregion, the second forbidden region and the third forbidden region(S08).

Furthermore, at least one of the first wiring, the second wiring, thethird wiring and the fourth wiring is expanded into the third forbiddenregion where the first forbidden region and the second forbidden regionoverlap each other (S08). Consequently, one of the first wiring, thesecond wiring, the third wiring and the fourth wiring is drawn in allthe regions on the plane. Thereby, the space between the first wiringand the second wiring, the space between the first wiring and the fourthwiring, and the space between the second wiring and the third wiring aremade to be prescribed widths.

Next, a trim pattern covering the third forbidden region is extractedfrom the plane (S09). In addition to the third forbidden region, thetrim pattern may include the region where the third wiring is drawn (thefirst forbidden region) and the region where the fourth wiring is drawn(the second forbidden region).

Next, a mandrel pattern including the first wiring and the third wiringis extracted among the first wiring, the second wiring, the third wiringand the fourth wiring drawn on the plane (S10), and the mask design iscompleted. Alternatively, a mandrel pattern including the second wiringand the fourth wiring may be extracted therefrom.

It may be possible to use other flow not including the counter “k”, inwhich the designer instructs the controller in the computer to proceedto S05 when completing the design.

FIG. 78A to FIG. 78C are plan views explaining a first rule of the maskdesign according to the embodiment. FIG. 78A shows terminals A and Bdisplayed on a base grid 810. FIG. 78B shows a first wiring 801connecting two terminals A. FIG. 78C shows a second wiring 803connecting two terminals B, which is drawn in addition to the firstwiring 801.

As shown in FIG. 78A, the base grid 810 includes a grid EC(i,j) disposedin a matrix of 5 rows and 5 columns. The designer inputs a pathway ofthe first wiring 801, specifying in sequence, for example, gridsEG(1,2), EG(2,2) and EG(3,2).

As shown in FIG. 78B, the controller displays the first wiring 801having the terminal A displayed in EG(1,2) as a start point, accordingto the pathway inputted by the designer. Then, the first forbiddenregion is set in a region adjacent to the first wiring 801 (S01).Specifically, grids EG(1,1), EG(2,1), EG(3,1), EG(1,3), EG(2,3), EG(3,3)and EG(4,2) in contact with grids EG(1,2), EG(2,2) and EG(3,2)displaying the first wiring 801 are specified as a first forbidden grid811 (a first grid), and are displayed as being distinguished from othergrids. For example, the grids are displayed with a changed color.

Here, the case that grids are “in contact with each other” also includesa case where corners of neighboring grids are in contact with eachother, in addition to a case where sides of neighboring grids are incontact with each other.

Subsequently, as shown in FIG. 78C, the controller displays the secondwiring 803 having the terminal B displayed in EG(1,4) as a start point,according to the pathway inputted by the designer. Then, the secondforbidden region is set in a region adjacent to the second wiring 803(S02). Specifically, grids EG(1,5), EG(2,5), EG(3,5), EG(4,5) andEG(5,4) in contact with grids EG(1,4), EG(2,4) and EG(3,4) displayingthe second wiring 803 are specified as a second forbidden grid 813 (asecond grid), and are displayed as being distinguished from other grids.For example, the grids are displayed with a different color or with adifferent hatching.

On the other hand, grids EG(1,3), EG(2,3), EG(3,3) and EG(4,3) betweenthe first wiring 801 and the second wiring 803 are a region where thefirst forbidden region and the second forbidden region overlap eachother. Accordingly, grids EG(1,3), EG(2,3), EG(3,3) and EG(4,3) aredisplayed distinguished from other grids as a third forbidden grid 815(a third grid) (S03).

FIG. 79A and FIG. 79B are plan views explaining a second rule of maskdesign according to the embodiment. FIG. 79A is a plan view showing astate where the first wiring 801, the second wiring 803, the firstforbidden grid 811, the second forbidden grid 813 and the thirdforbidden grid 815 are displayed on the base grid 810. Grids EG(5,1) toEG(5,5) are vacant grids where none of these are displayed.

In the embodiment, the third wiring 805 is displayed on the secondforbidden grid 813 (S05). In addition, the fourth wiring 807 isdisplayed on the first forbidden grid 811 (S06). Then, on vacant gridsother than the grid on which the first wiring 801 is displayed, the gridon which the second wiring 803 is displayed, the first forbidden grid811, the second forbidden grid 813 and the third forbidden grid 815, oneof the third wiring 805 and the fourth wiring 807 is displayed (S07).

In the example shown in FIG. 79B, a third wiring 805 a is displayed onthe grids EG(5,1) to EG(5,5) that are vacant grids. In other words, inthe example, the third wiring 805 displayed in the second forbiddenregion 813 is expanded into the vacant grids.

FIG. 80A to FIG. 80C are schematic plan views explaining a third rule ofthe mask design according to the embodiment.

In FIG. 80A, the first wiring 801, the second wiring 803, the thirdwiring 805 and the fourth wiring 807 are displayed on the base grid 810.No wiring is displayed on the third forbidden grid 815.

Next, FIG. 80B is a plan view showing a state where the first wiring 801is displayed on the third forbidden grid 815. For example, an expandedpart 801 d is displayed expanding the first wiring 801 on the third grid815.

In the embodiment, on the third forbidden grid 813, the expanded part801 d is displayed expanding at least one of the first wiring 801, thesecond wiring 803, the third wiring 805 and the fourth wiring 807 (S08).

Furthermore, as shown in FIG. 80C, the expanded part 801 of the firstwiring 801 may be expanded to connect the first wiring 801 with thethird wiring 805. That is, at least one of the first wiring 801, thesecond wiring 803, the third wiring 805 and the fourth wiring 807displayed on the first forbidden grid may be expanded to connect thefirst wiring 801 with the third wiring 805, or to connect the secondwiring 803 with the fourth wiring 807. Consequently, a wiring patterncan be designed so that the space between the first wiring 801 and thesecond wiring 803, the space between the first wiring 801 and the fourthwiring 807, and the space between the second wiring 803 and the thirdwiring 805 are prescribed spaces.

FIG. 81A and FIG. 81B are schematic plan views showing a method forextracting the trim pattern. FIG. 81A and FIG. 81B show an example ofextracting the trim pattern from the base grid 810 shown in FIG. 80C.

For example, as shown in FIG. 81A, a trim pattern 821 covering theexpanded part 801 d of the first wiring 801 is extracted. In otherwords, the trim pattern 821 covering the third forbidden grid 815 isextracted (S09).

In addition, as shown in FIG. 81B, a trim pattern 823 including a part823 a covering the expanded part 801 d, a part 823 b covering the thirdwiring 805 and a part 823 c covering the fourth wiring 807 may beextracted.

Next, FIG. 82A to FIG. 82C are plan views showing a method forextracting the mandrel pattern. FIG. 82A shows the base grid 810displaying the first wiring 801, the second wiring 803, the third wiring805 and the fourth wiring 807. In the example, the first wiring 801 isconnected with the third wiring 805.

For example, as shown in FIG. 82B, a mandrel pattern 831 including thefirst wiring 801 and the third wiring 805 may be extracted (S10).Alternatively, a mandrel pattern 833 including the second wiring 803 andthe fourth wiring 805 may be extracted as shown in FIG. 82C. Next, aspecific layout procedure according to the first rule of the embodimentis explained referring from FIG. 83 to FIG. 94. FIG. 83 to FIG. 99C areschematic plan views showing a process of mask design according to theembodiment.

FIG. 83 is a plan view illustrating a base grid 800 according to theembodiment. The base grid 800 is displayed, for example, on the screenof the display unit. The base grid 800 shown here includes a gridDG(i,j) (1≤i≤8, 1≤j≤8) disposed in a matrix of 8 rows and 8 columns. Thegrid DG(i,j) is set, for example, to be a size corresponding to exposurelimit of photolithography. In the example, it is 60 nm.

As shown in FIG. 83, the controller displays, for example, terminals Ato D on the base grid 800 on the basis of design information. TerminalsA to D may be inputted by specifying the grid DG(i,j) on the screen bythe designer using a pointer. Here, terminals A to D may be set to be apart where a contact is disposed. The total number n of wirings can bedetermined by the disposition of contacts. For example, in the case ofFIG. 83, a contact is disposed for terminals A to D, and, when terminalsA to D are connected with wiring, the total number of wirings isdetermined to be four.

For example, a terminal displayed within the grid DG(i,j) shows simply astart point or an end point of a wiring. On the other hand, it is shownthat each of terminals B and D displayed spreading over four gridsDG(i,j) serves as a pad.

FIG. 84 and FIG. 85 are schematic plan views showing a process fordrawing the first wiring 801 on the base grid 800.

The designer inputs the pathway of the first wiring 801, specifying inorder from a grid DG(5,3) displaying the terminal A to DG(5,4), DG(5,5),DG(5,6) and DG(5,7).

As shown in FIG. 84, the controller displays the first wiring 801 ongrids DG(5,3), DG(5,4), DG(5,5), DG(5,6) and DG(5,7). The line width ofthe first wiring 801 is displayed, for example, in accordance with anactual wiring size. In this case, the line width of the first wiring 801is 30 nm.

Grids DG(4,2) to DG(4,6), DG(5,2) and DG(6,2) to DG(6,6) in contact withthe grid displaying the first wiring 801 are displayed as the firstforbidden grid 811.

Subsequently, as shown in FIG. 85, grids DG(6,7) and DG(6,8) arespecified to establish the pathway of the first wiring 801. That is,when the designer specifies the grid DG(6,8) displaying the terminal Aof the end point, the pathway of the first wiring 801 is established.

The controller displays the first wiring 801 running from the startpoint to the end point, and displays grids DG(7,4), DG(8,4), DG(8,5) andDG(7,6) to DG(7,8) as the first forbidden grid 811.

FIG. 86 to FIG. 88 are plan views showing a process for drawing thesecond wiring 803 on the base grid 800.

The designer inputs the pathway of the second wiring 803, specifying inorder from a grid DG(5,4) displaying the terminal B to DG(4,4), DG(4,3),DG(4,2), DG(5,2) and DG(6,2). In this case, the first wiring 801 can notbe drawn, since the grid DG(5,4) is the first forbidden grid 811.

For example, grids displaying two terminals are neither the firstforbidden grid 811 nor the second forbidden grid 813, and the pathwayconnecting the two terminals does not include the first forbidden grid811 and the second forbidden grid 813, either of the first wiring 801and the second wiring 803 may be selected.

As shown in FIG. 86, the controller displays the second wiring 803 ongrids DG(5,4), DG(4,4), DG(4,3), DG(4,2), DG(5,2) and DG(6,2).

Subsequently, the designer specifies grids DG(6,3), DG(6,4), DG(6,5) andDG(7,6), and establishes the pathway of the second wiring 803.

As shown in FIG. 87, the controller displays the remaining part of thesecond wiring 803 on grids DG(6,3), DG(6,4), DG(6,5), DG(6,6), DG(7,5)and DG(7,6).

For example, when grids DG(6,5) and DG(7,6) are specified, thecontroller determines that grids DG(7,5) and DG(6,6) are also wiringregions. Then, it displays a pad spreading over the four grids.

Next, as shown in FIG. 88, a vacant grid (a fourth grid) in contact withthe second wiring 803 is displayed as the second forbidden region 813.Here, the “vacant grid” indicates a grid on which the first wiring 801and the second wiring 803 are not displayed and which is not displayedas the first to third forbidden regions.

Furthermore, the controller displays grids DG(4,6) and DG(7,7) incontact with both the grid displaying the first wiring 801 and the griddisplaying the second wiring 803, distinguishing from other grids as thethird forbidden grid 815.

FIG. 89 to FIG. 94 are schematic plan views showing a process fordrawing a subsequent first wiring 801 on the base grid 800. Hereinafter,the first wiring displayed first is distinguished from the first wiringto be displayed subsequently by being referred to as the first wiring801 a and the first wiring 801 b, and the first wiring 801 c,respectively. In addition, the first wirings 801 a to 801 c areoccasionally referred to as the first wiring 801 collectively.

The designer inputs the pathway of the first wiring 801 b, specifying inorder from the grid DG(7,3) displaying the terminal C to DG(7,4) andDG(8,4). Since the grid DG(7,3) is the second forbidden grid 813, thesecond wiring 803 can not be drawn.

As shown in FIG. 89, the controller displays the first wiring 801 b ongrids DG(7,3), DG(7,4) and DG(8,4).

Subsequently, the designer specifies grids DG(8,5), DG(8,6) and DG(8,7),and establishes the pathway of the first wiring 801 b.

As shown in FIG. 90, the controller displays the remaining part of thefirst wiring 801 b on grids DG(8,5), DG(8,6) and DG(8,7).

Next, as shown in FIG. 91, vacant grids DG(8,2), DG(8,3) and DG(8,8) incontact with the first wiring 801 b are displayed as the first forbiddenregion 811.

Furthermore, the controller displays the grid DG(7,2) in contact withboth the grid displaying the first wiring 801 b and the grid displayingthe second wiring 803 as the third forbidden grid 815, distinguishingthem from other grids.

Next, the designer inputs the pathway of the first wiring 801 c,specifying in order from the grid DG(2,6) displaying the terminal D toDG(2,5) and DG(2,4). Grids displaying the terminal D, DG(3,2) andDG(3,3) are the second forbidden grid 813. Therefore, the second wiring803 can not be drawn.

As shown in FIG. 92, the controller displays the first wiring 801 c ongrids DG(2,6), DG(2,5) and DG(2,4).

Subsequently, the designer specifies grids DG(2,3), DG(3,2) and DG(2,1),and establishes the pathway of the first wiring 801 c.

As shown in FIG. 93, the controller displays the remaining part of thefirst wiring 801 b on grids DG(2,3), DG(2,2), DG(2,1), DG(3,3) andDG(3,2).

Next, as shown in FIG. 94, vacant grids DG(1,1) to DG(1,7), DG(2,7) andDG(3,7) in contact with the first wiring 801 c are displayed as thefirst forbidden region 811.

Furthermore, the controller displays grids DG(3,1), DG(3,4), DG(3,5) andDG(3,6) in contact with both the grid displaying the first wiring 801 cand the grid displaying the second wiring 803 as the third forbiddengrid 815, distinguishing them from other grids.

Next, using FIG. 95 to FIG. 97, a specific layout procedure on the basisof the second rule is explained.

FIG. 95 is a schematic plan view showing a process for drawing the thirdwiring and the fourth wiring on the base grid 800.

On the base grid 800, the first wirings 801 a, 801 b and 801 c, thesecond wiring 803, the third wiring 805 and the fourth wiring 807 aredisplayed. In the example, on vacant grids DG(1,8), DG(2,8), DG(3,8) andDG(8,1), the fourth wiring 817 is displayed. For example, the fourthwiring 817 displayed on the vacant grid is a part obtained by extendingor expanding the fourth wiring 807 displayed on the first forbidden grid811.

FIG. 96 and FIG. 97 are plan views showing a process for expanding thesecond wiring so that the space between the first wiring 801 and thesecond wiring 803 becomes a prescribed space on the base grid 800.

As shown in FIG. 96, the second wiring 803 is displayed on the thirdforbidden grid 815. For example, the second wiring 803 is expanded to beextended on the third forbidden grid 815.

Subsequently, as shown in FIG. 97, the second wiring 803 displayed onthe third forbidden grid 815 is extended to connect the second wiring803 with the fourth wiring 807.

In the example, the second wiring 803 is displayed on the thirdforbidden grid 815, but the mode is not limited to this. For example, itis also possible to display the fourth wiring 807 on the third forbiddengrid 803, and to connect the second wiring 803 with the fourth wiring807. In addition, it is also possible to display either of the firstwiring 801 and the third wiring 805 on the third forbidden grid 815, andto connect the first wiring 801 with the third wiring 805.

FIG. 98 is a plan view showing a state where a trim pattern 824 isextracted from the base grid 800 shown in FIG. 97. The trim pattern 824includes a part 824 a covering the expanded part of the second wiring803, a part 824 b covering the third wiring 805 and a part 824 ccovering the fourth wiring 807.

That is, the controller displays the grid displaying the third forbiddengrid 815 and the third wiring, and the grid displaying the fourthwiring, distinguishing them from other grids. For example, it may bepreferable to change the color of each grid.

FIG. 99A to FIG. 99C are schematic plan views showing the extraction ofthe mandrel pattern in the base grid 800. FIG. 99A shows the same gridsas the base grid 800 shown in FIG. 97. The first wiring 801, the secondwiring 803, the third wiring 805 and the fourth wiring 807 are shown,and the second wiring 803 is connected with the fourth wiring 807.

For example, as shown in FIG. 99B, the second wiring 803 and the fourthwiring 807 are extracted from the base grid 800 shown in FIG. 99A.Subsequently, as shown in FIG. 99C, the grid displaying the secondwiring 803, and the grid displaying the fourth wiring 807 are displayedas being distinguished from other grids. Consequently, a mandrel pattern841 can be extracted including the second wiring 803 and the fourthwiring 807.

According to the second rule of mask design, the third wiring 805 or thefourth wiring 807 is expanded to the vacant spaces excluding the regionwhere the first wiring is drawn, the region where the second wiring isdrawn, the first forbidden region, the second forbidden region and thethird forbidden region, after completing the drawing of the first wiringand the second wiring, but the embodiment is not limited thereto. Forinstance, it may be possible to sequentially dispose another thirdwiring and fourth wiring in the vacant places. In addition, it may bepossible to set a maximum allowable line width for the third and fourthwiring.

FIGS. 100A to 101C are schematic plan views showing another rules of themask design. In this example, the base grid 820 includes a grid EC(i,j)disposed in a matrix of 6 rows and 8 columns.

The first wiring 801 and the second wiring 803 are displayed in the basegrid 820 shown in FIG. 100A. The first forbidden region 811 has been seton the grids EG(1,3) to EG(6,3) that are adjacent to the first wiring801 displayed on the grids EG(1,2) to EG(6,2), and the second forbiddenregion 813 has been set on the grids EG(1,7) to EG(6,7) that areadjacent to the second wiring 803 displayed on the grids EG(1,8) toEG(6,8). The grids EG(1,4) to EG(6,6) between the first forbidden region811 and the second forbidden region 813 are the vacant grids. Here, thecase specifying a pair of grids at diagonal corners of square regionmeans specifying all grids included therein.

FIG. 100B shows the base grids 820, in which the fourth wiring 807 isdisplayed on the first forbidden grids 811 shown in FIG. 100A, and thethird wiring 805 is displayed on the second forbidden grids 813.According to the second rule, the fourth wiring 807 is expanded to thevacant grids EG(1,4) to EG(6,6), so that the distance between the thirdwiring 305 and the fourth wiring 307 is set to be the prescribeddistance. In this case, the area combining the second wiring 803 and thefourth wiring 807 becomes larger than the area combining the firstwiring 801 and the third wiring 803.

On the other hand, it may be possible to expand both the third wiring805 and the fourth wiring 807. In FIG. 100C, the fourth wiring 807displayed on the first forbidden grids 811 is expanded to the vacantgrids EG(1,4) to EG(5,6), and the third wiring 805 displayed on thesecond forbidden grids 813 is expanded to the vacant grids EG(1,6) toEG(6,6). Then, the distance between the third wiring 305 and the fourthwiring 307 is set to be the prescribed distance. Furthermore, the areacombining the second wiring 803 and the fourth wiring 807 becomesequivalent to the area combining the first wiring 801 and the thirdwiring 803. Thereby, it may become possible to improve accuracy ofpattern transfer in the photolithography and etching process of wiring.

FIG. 101A shows another base grid 820, in which the first wiring 801 andthe second wiring 803 are alternately displayed in the verticaldirection. The grids between the first wiring 801 and the second wiring803, i.e. grids EG(2,1) to EG(2,8) and grids EG(5,1) to EG(5,8) are setto be the third forbidden grids. Therefore, a new grid cannot bedisplayed thereon.

In regard to this, it may be preferable to convert the first wiring 801,displayed on the grids EG(4,1) to EG(4,8), to the second wiring 803, andto convert the second wiring 803 displayed on the grids EG(3,1) toEG(3,8), to the first wiring 801, as shown in FIG. 101B. Thereby, thethird forbidden grids 815 set on the grids EG(2,1) to EG(2,8) isconverted to the first forbidden grids 811, and the third forbiddengrids 815 set on the grids EG(5,1) to EG(5,8) is converted to the secondforbidden grids 813.

Then, it becomes possible to display the fourth wiring 807 on the firstforbidden grids 811 set on the grids EG(2,1) to EG(2,8), and to displaythe third wiring 805 on the second forbidden grids 813 set on the gridsEG(5,1) to EG(5,8), as shown in FIG. 101C. Thus, it is preferable toconvert the first wiring 801 and the second wiring 803 to each other,after completing the design of the first and second wirings, and therebyto increase number of the wirings.

In the embodiment described above, the pathway of the wiring is manuallyinputted between the start point and the end point, and the controllerdisplays the wiring according to the inputted information. Theembodiment is not limited thereto. For instance, it may be possible toautomatically establish the pathway of the wiring by way of applyingautomatic wiring algorism, such as a maze solving algorism, usinginformation of the start grid and the end grid given as a netlist.

It may also be possible to apply an automatic wire-routing algorismminimizing the number of the third forbidden grids as a cost parameter.For instance, when applying the maze solving algorism and like, theautomatic wire-routing algorism may seek a pathway for both the firstwiring and the second wiring, since the grids available for each of thefirst and second wirings are different from each other. Consequently,the pathway or the wiring that makes the number of the third forbiddengrids minimum is selected from a plurality wiring pathways.

Alternatively, it may be possible to use a method that converts thefirst wiring and the second wiring to one another after completing thedesign of the first and second wiring or in the procedure of the wiringdesign. For instance, it may be advantageous to seek a combination ofthe first wiring and the second wiring by applying a binary integerprogramming using the selection of the first wiring or the second wiringas a parameter, and to determine the combination which makes the numberof the third forbidden grids minimum.

In the example described above, the wirings are displayed on the grids,but the embodiment is not limited thereto. It may be possible to set thefirst forbidden region and the second forbidden region, which have thewidth corresponding to the exposure limit of the photolithography, inthe space surrounding the first wiring 801 and the second wiring 803.

FIGS. 102A and 104B are schematic plan views showing a rule of maskdesign according to a variation of the eighth embodiment. In theseexamples, the grids are not displayed on the screen of the display unit.

The designer may instruct the controller in the computer to display thefirst wiring 801 and the second wiring 803 as shown in FIG. 101A, eachof which connects a pair of points set on arbitrary positions on thescreen. Then, the controller sets the first forbidden region 811adjacent to a first wiring region 831 and the second forbidden region813 adjacent to a second wiring region 833. The first wiring region 831and the second wiring region 833 include the first wiring 801 and thesecond wiring 803 respectively, and may have the width corresponding tothe exposure limit of the photolithography.

As shown in FIGS. 102A and 102B, in the case where the first forbiddenregion 811 does not overlap the second forbidden region 813, the fourthwiring 807 is displayed on the first forbidden region 811, and the thirdwiring 805 is displayed on the second forbidden region 813. The same mayapply to the case where the first forbidden region 811 is set to beseparated from the second forbidden region 813.

In the case where the first forbidden region 811 overlaps the secondforbidden region 813 at least in part, the controller sets the thirdforbidden region 815 on a space including the overlapping portionbetween the first wiring region and the second wiring region as shown inFIGS. 103A and 104A.

In the example shown in FIG. 103A, a width of the overlapping portion835 is the same as each width of the first forbidden region 811 and thesecond forbidden region 813. In the example shown in FIG. 104A, theoverlapping portion 835 is narrower than each of the first forbiddenregion 811 and the second forbidden region 813.

Subsequently, as shown in FIGS. 103B and 104B, the controller expandsone of the first wiring 801 and the second wiring 803 to the thirdforbidden region 815, whereby a distance between the first wiring 801and the second wiring 803 becomes the prescribed distance.

FIGS. 105A and 105B are schematic views showing the mask designsaccording to the eighth embodiment. FIG. 105A shows the case where thescreen includes the grids set thereon. FIG. 105B shows the case wherethe screen includes no grids thereon.

In the example shown in FIG. 105A, the terminals A to D and the pathwaysof wiring are designed according to the rule based on the grids. Incontrast to this, in the example shown in FIG. 105B, the terminal can beset on an arbitrary position on the screen, and a pathway of the wiringis flexibly set therebetween. That is, the mask design shown in FIG.105B has larger flexibility than that shown in FIG. 105A.

Next, referring to FIG. 106A to FIG. 108C, the method for manufacturinga semiconductor device according to the eighth embodiment is explained.FIG. 106A to FIG. 108C are schematic plan views showing themanufacturing process of a semiconductor device according to the eighthembodiment.

FIG. 106A is a plan view showing a mandrel 901 formed on a wafer 900.The mandrel 901 is, for example, a first insulating film having etchingselectivity for an underlying layer 903.

For example, on the first insulating film provided on the underlyinglayer 903, an etching mask is formed by transferring a mandrel pattern841 shown in FIG. 99C. Subsequently, the first insulating film is etchedselectively to form the mandrel 901 on the underlying layer 903. Forexample, the line width of the mandrel 901 is 60 nm, which is theexposure limit in photolithography.

Next, as shown in FIG. 106B, the mandrel 901 is slimmed so that the linewidth becomes 30 nm. For example, the first insulating film isover-etched while an etching mask is left on the mandrel 901.Consequently, the line width of the mandrel 901 can be made to have awidth not more than the exposure limit of photolithography.

Next, as shown in FIG. 107A, a sidewall 905 is formed on the side faceof the mandrel 901. For example, a second insulating film covering themandrel 901 is formed on the wafer 900. Subsequently, using an RIEmethod, the second insulating film is etched selectively to form thesidewall 905 composed of the second insulating film on the side face ofthe mandrel 901. Material having etching selectivity for the mandrel 901is used for the second insulating film.

For example, the second insulating film is etched under such ananisotropic condition, where an etching rate in the directionperpendicular to the wafer face is larger than an etching rate in thedirection parallel to the wafer face. Consequently, the secondinsulating film formed on the mandrel 901 and on the underlying layer903 can be selectively etched, while leaving the sidewall 905 on theside face of the mandrel 901.

Subsequently, as shown in FIG. 107B, the mandrel 901 is removed whileleaving the sidewall 905 on the underlying layer 903.

Next, as shown in FIG. 108A, for example, a resist mask 911 is formed onthe wafer 900. The trim pattern 824 has been transferred on the resistmask 911.

Next, using the sidewall 905 and the resist 911 as etching masks, theunderlying layer 903 is etched, for example, using an RIE method.Subsequently, the resist 911 and the sidewall 905 are removed.Consequently, as shown in FIG. 108B, a wiring trench 903 a is formed inthe underlying layer 903.

Next, a metal layer is formed on the underlying layer 903. For example,a metal layer having a stacked structure of a barrier layer containingtungsten and a wiring layer containing copper is formed. Subsequently,the surface of the metal layer is removed, for example, using a CMP(Chemical Mechanical Polishing) method to expose the underlying layer903. Consequently, as shown in FIG. 108C, it is possible to form awiring 907 having the so-called damascene structure embedded in thewiring trench 903 a.

The wiring 907 formed through the above process has a line width smallerthan the exposure limit of photolithography. That is, a highlyintegrated semiconductor device can be realized using the manufacturingmethod according to the embodiment.

The method of mask design according to the embodiment facilitates thedesign of wiring layout used in the sidewall method. Since no basepattern is used in the embodiment, degree of freedom in design is large.Consequently, the time necessary for designing wiring layout can beshortened to improve the manufacturing efficiency.

Ninth Embodiment

Next, a ninth embodiment will be described with reference to FIG. 109Ato FIG. 113.

A method for automatically designing a wiring layout will be describedaccording to the embodiment, which is used for a 2-time sidewall method.

For example, a designer inputs a start point and an end point of thewiring into the input unit shown in FIG. 49. The computer generates anappropriate wiring on the basis of the start point and the end point,and displays a layout thereof on the display unit. In this example, thewiring layout design is performed using the sidewall wiring base grid700 described in the seventh embodiment. The base grid 700 includes bluegrids B, red grids R, green grids G, and three kinds of colorless gridsC, M, N. The same color grid connects each other, which result in thewiring layout including, for example, a blue wiring connecting the bluegrids B, a red wiring connecting the red grids R, and a green wiringconnecting the green grids G.

In the embodiment, the following seven rules are used for connectinggrids.

-   -   (1) A start point and an end point of a wiring are grids with        the same color.    -   (2) The wiring connecting the start point and the end point        passes through grids with the same color as the color of the        start point and the end point. In regard to the colorless grids,        the rules (4) to (6) below refer thereto.    -   (3) The colorless grids through which the wiring passes become        exchanged grids with the same color as the color of the start        point and the end point.    -   (4) The blue or red wiring may pass through the grids C among        the three colorless grids C, M, N.    -   (5) The blue or green wiring may pass through the colorless        grids M.    -   (6) The red or green wiring may pass through the colorless grids        N.    -   (7) When the green wiring connects the grids G and the pathway        of the green wiring is bent, the red grids R or the blue grids B        are located inside the corner at the turning point of the        pathway of the green wiring.

FIG. 109A to FIG. 109C are schematic views showing examples of thepathway of the green wiring. FIG. 109A shows the seventh rule. As shownby a dotted line in FIG. 109A, a turn of the wiring is not allowed,where a colorless grid Cex locates inside a corner at the turning pointof the pathway of the green wiring.

In FIG. 109B, each of two pathways of the green wiring connects a startpoint and an end point with a bent, where a colorless grid Cex locatesinside a corner at the turning point of the pathway of the green wiring.Therefore, the pathways shown in FIG. 109B are not allowed. On the otherhand, in the example shown in FIG. 109C, two pathways of the greenwiring connect a start point and an end point, and each pathway has abent, where a red grid Rex locates inside the corner at the turningpoint of the pathway of the green wiring. Thus, the wiring layouts shownin FIG. 109C are allowed.

Next, an example of wiring designs according to the embodiment will bedescribed with reference to FIG. 110 to FIG. 113. In this example, agreen wiring among blue, red, and green wirings is designed in first,where the rule of turning pathway is added. Thereby, it may be possibleto reduce number of isolated grids.

First, as shown in FIG. 110, the designer specifies the grid (terminal)serving as a start point or an end point of each wiring on the base grid700. In this example, the designer specifies three terminals B1 servingas the start point or the end point of the blue wiring, three terminalsR1 serving as the start point or the end point of the red wiring. Thedesigner also specifies terminal pairs G1 to G5, and each terminal pairserves as a start point and an end point of a green wiring. As shown inthe figure, two grids are specified for each of the terminal pairs G1 toG5.

As shown in FIG. 111, the computer designs the green wiring connectingeach of terminal pairs G1 to G5 in accordance with the rules (1) to (7).At this time, it is preferable to design a green wiring so as not tocross a blue or red wiring, which is designed later, and so as not tocross other green wiring. In this example, the pathways are designed sothat the same wirings are provided as the wiring layout shown in FIG.69A, however it is not limited thereto.

Next, as shown in FIG. 112, the computer designs the blue wiringconnecting the terminals B1, and the red wiring connecting the terminalsR1. For example, the blue wiring is designed so as to have one of thethree terminals B1 taken as the start point, and remaining two taken asthe end point. Subsequently, the red wiring is designed so as to haveone of the three terminals R1 taken as the start point, and remainingtwo taken as the end point.

Either of the blue wiring and the red wiring may be designed in first.The blue wiring and the red wiring are designed so as not to cross eachother, and both are designed so as not to cross the green wiring.

Next, the computer selects one of the blue wiring and the red wiring asthe mandrel. For example, when the blue wiring is selected as themandrel, a blue dummy wiring is designed, connecting grids B on whichthe blue wiring connecting the three terminals B1 does not provided.Furthermore, all grids B are connected to each other so that each grid Bis connected to the adjacent one located at the connectable position.The computer designs the blue dummy wiring so as not to cross the redand green wirings. Then, the computer disposes one-line cutting patternsX_(c1) on grids C, each of which locates at a position between the bluewiring and the blue dummy wiring.

Subsequently, the computer designs a red dummy wiring connecting betweenthe grids R, on which the red wiring is not provided. All grids R areconnected to each other so that each grid R is connected to the adjacentone, which locates at the connectable position. The computer designs thered dummy wiring so as not to cross the blue wiring, the blue dummywiring, and the green wiring. When the red wiring is selected as themandrel, the one-line cutting patterns X_(c1) are disposed on the gridsC, each of which locates at a position between the red wiring and thered dummy wiring.

Next, as shown in FIG. 113, the computer designs green dummy wirings,each of which connects the grids G not included in the green wiringseach connecting any one of the terminal pairs G1 to G5. The computerarranges an one-line cutting patterns X_(c2) on the grids M and N, eachof which locates at a position between one of the terminals G1 to G5 andthe green dummy wiring adjacent thereto.

Through the above process, the computer may generate automatically thewiring layout shown in FIG. 69A, wherein the designer only specifies thestart point and the end point of the wiring. Then, for example, asemiconductor device may be manufactured using the process shown in FIG.70A to FIG. 75B. In this process, a resist 709 is provided at portionscorresponding to the grids M and N, where the one-line cutting patternX_(c2) is disposed. Thereby, it is possible to cut a wiring 715 at aposition where the one-line cutting pattern X_(c2) is disposed.

At this point, this embodiment shows that the green wiring is designedfirst of all. However it is possible to design the blue wiring or thered wiring before designing the green wiring. In other words, a sequenceof designing the wirings may not only depend on the color differencethereof. For example, the computer may design the wirings according arandom order, such as a first blue wiring, a first green wiring, asecond blue wiring, a first red wiring . . . .

Tenth Embodiment

Next, a tenth embodiment will be described with reference to FIG. 114Ato FIG. 127. In the embodiment, an exemplary wiring process isdescribed, which is different from a damascene process, and applied forforming wirings beneath a mask for selectively removing metal layer.FIG. 114A to FIG. 115F are schematic views showing a manufacturingprocess of a semiconductor device according to the tenth embodiment.FIG. 116 to FIG. 121 are plan views showing a method for designing awiring layout according to the embodiment. FIG. 122 to FIG. 127 areschematic views showing a process of forming a wiring pattern accordingto the embodiment.

As shown in FIG. 114A and FIG. 114D, a metal layer 1003 is formed on anunderlying layer 1001, and a mandrel 1005 is provided thereon. FIG. 114Ais a plan view showing an upper surface of the metal layer 1003, andFIG. 114D is a cross-sectional view taken along B-B line in FIG. 114A.The relationship between the plan view and the section view is much thesame for views showing following processes.

The underlying layer 1000 is, for example, an interlayer insulatingfilm, and the metal layer 1003 is, for example, a tungsten layer. Awidth of the mandrel 1005 is, for example, a critical width “d” of thewiring pattern capable of being formed by photolithography, and spacingbetween the adjacent mandrels 1005 is also provided with a width around“d”.

Next, as shown in FIG. 114B and FIG. 114E, the mandrel 1005 is subjectedto slimming, and the line width is provided with a width around “d”/2.

Subsequently, as shown in FIG. 114C and FIG. 114F, a side wall(insulating film 1007) is formed on a side surface of the mandrel 1005.The insulating film 1007 is formed to have a width around “d”/2, forexample. Thereby, a space with the width around “d”/2 is providedbetween the adjacent mandrels 1005 via the side walls provided on eachside surface thereof.

Next, as shown in FIG. 115A and FIG. 115D, the mandrel 1005 isselectively removed. Thereby, the side wall 1007 is left on the metallayer 1003. A width of the side wall 1007 and spacing between the sidewalls 1007 adjacent to each other are provided to be around “d”/2,respectively.

Next, as shown in FIG. 115B and FIG. 115E, for example, a resist 1009 isformed so as to cover the metal layer 1003 having the side wall 1007.The resist 1009 has an opening 1009 a, and part of the side wall 1007 isexposed inside the opening 1009 a. Subsequently, the exposed part of theside wall 1007 is removed by etching, wherein the resist 1009 serves asa mask. The resist 1009 may be formed so as to have the opening 1009 a,for example, using the trimming mask of the sixth and seventhembodiments.

Subsequently, the resist 1009 is removed, and the metal layer 1003 isetched using the side wall 1007 as a mask. Thereby, as shown in FIG.115C and FIG. 115F, a wiring 1010 is formed on the underlying layer1001. The wiring 1010 has a width of about “d”/2 and spacing between theadjacent wirings has also the width around “d”/2.

In the manufacturing method according to the embodiment, a portion onwhich the mandrel 1005 is formed provides a space between the wirings.

Next, a method for designing the wiring mask used for the manufacturingprocess above will be described with reference to FIG. 116 to FIG. 121.In the embodiment, the wiring layout is also designed using the sidewall wiring base grid 700. As described in the seventh embodiment andthe other embodiment, the base grid 700 includes the blue grid B, thered grid R, the green grid G, and three kinds of colorless grids C, M, N(see FIG. 68A).

As shown in FIG. 116, a pair of terminals G1 is disposed respectively ontwo green grids. Terminals G2 to G5 are also disposed on the other greengrids G in the same manner. For example, it is preferable that one ofthe terminals G1 is a start point of two-terminal-pair network, and anend point thereof. Each of terminal pair G2 to G5 also includes a startpoint and an end point of the two-terminal-pair network.

Next, as shown in FIG. 117, the green wiring GL is formed so as toconnect terminal pair G1 in accordance with the rules described, forexample, in the seventh or ninth embodiment. Subsequently, the othergreen wirings GL are formed so as to connect each of the terminal pairG2 to G5. The green wirings GL each connecting different terminal pairare formed so as not to cross each other. In this example, the greenwirings GL are provided with the same pathways as the ones shown in FIG.69A. However, it is not limited thereto, and another pathway may beselected.

Next, as shown in FIG. 118, the blue wiring is formed so as to connectblue grids B to each other, and the red wiring is formed so as toconnect red grids R to each other. All blue grids B and all red grids Rare respectively connected to each other, and the wiring paths areprovided on all of the colorless grids C. The blue wiring and red wiringare formed not to cross one another, and not to cross the green wiringsGL.

Next, as shown in FIG. 119, dummy green wirings GD are formed byconnecting green grids G on which the green wiring GL is not provided.Furthermore, dummy wirings GDC are disposed on the colorless grids M andN each located between one of terminals G1 to G5 and a green dummywiring GD adjacent thereto. Thereby, all green grids G are connected toeach other, and thus the wirings are provided on all colorless grids Mand N.

Next, as shown in FIG. 120, cut patterns CP are extracted to cover thegreen dummy wirings GD and GDC using the method for forming a trimmingmask described in the sixth embodiment, for example.

FIG. 121 is a layout that shows the blue wirings and the red wiringsextracted from the wiring layout in FIG. 119. Either of the blue wiringsand the red wirings shown in the figure can be used as a mandrelpattern.

Next, examples of the layout pattern used in a manufacturing processaccording to the embodiment will be described.

In FIG. 121, the blue wirings are selected as the mandrel, and the maskpattern is formed, for example. FIG. 122 shows the mask pattern of themandrel, which is formed using the blue wirings. The mask pattern isprovided with a width around “d” (2F), for example.

Next, the mandrel 1005 is formed on the metal layer 1003 using the maskpattern of the mandrel shown in FIG. 122 (see FIG. 114A and FIG. 114D).Subsequently, as shown in FIG. 123, the mandrel 1005 is subjected toslimming, and provided with the width around “d”/2 (F).

Next, as shown in FIG. 124, a side wall 1007 is formed on a side surfaceof the mandrel 1005. The side wall 1007 is formed to have a width around“d”/2 (F), for example. Subsequently, as shown in FIG. 125, the mandrel1005 is selectively removed, leaving the side wall 1007 on the metallayer 1003.

Next, as shown in FIG. 126, a resist 1009 is formed so as to cover themetal layer 1003 and the side wall 1007 formed thereon (see FIG. 115B).The resist 1009 has the opening 1009 a corresponding to the cut patternCP. The opening 1009 a is provided with a width, for example, around “d”(2F), and thus it may be possible to be formed using photolithography.

Subsequently, unnecessary portions of the side wall 1007 are removed byetching, using the resist 1009 as a mask. Thereby, as shown in FIG. 127,wiring patterns are formed so as to connect each of terminal pairs G1 toG5. The wiring 1010 is formed by etching the metal layers 1003 using theside wall 1007 as a mask, and electrically connects each terminal pair(see FIG. 115C and FIG. 115F).

In this manner, the wiring layout is realized for implementing themanufacturing method where the wirings are formed beneath the side wall.

Eleventh Embodiment

A method of mask design according to an embodiment will be describedwith reference to FIG. 128 to FIG. 136.

FIG. 128 is a flow chart illustrating a process of mask design.

As shown in FIG. 128, the method of mask design according to theembodiment includes the following procedures.

1) A base grid including a plurality of grids G(m,n) is prepared. Theindexes m and n used here are positive integer. The base grid has, forexample, a structure in which the plurality of grids are disposed in m×nmatrix configuration (S21).

2) A plurality of pairs of terminals are disposed on the base grid(S22). More specifically, the grids G(m,n) on which the terminals aredisposed are assigned. Hereinafter, when not assigning positions of thegrids, the grid is referred to as grid G. Here, only one terminal isdisposed on one grid G.

3) A first wiring connecting between a first pair of terminals among theplurality of pairs of terminals is drawn on the base grid (S23). Thefirst wiring passes through at least one or more grids G and connectsone terminal of the first pair of terminals to the other terminal. Inother words, the first wiring shows one path connecting one of the firstpair of terminals to the other. The first wiring is not limited to one,but may be a plurality of first wirings connecting each pairs of firstterminals. The first wirings are drawn so as to separate from each othervia the three or more grids G.

4) A second wiring connecting between a second pair of terminals amongthe plurality of pairs of terminals is drawn on the base grid (S24). Thesecond wiring passes through at least one or more grids G and connectsone terminal of the second pair of terminals to the other terminal. Inother words, the second wiring shows one path connecting the one ofsecond pair of terminals to the other. The second wiring is not limitedto one, but may be a plurality of second wirings connecting each ofpairs of second terminals. The plurality of second wirings are drawn soas to separate from each other via three or more grids. The secondwiring is drawn so as to be separated from the first wiring via one ormore grids G.

5) A third wiring connecting between a third pair of terminals among thepairs of terminals is drawn on the base grid (S25). The third wiringpasses through at least one or more grids G and connects one terminal ofthe third pair of terminals to the other terminal. In other words, thethird wiring shows one path connecting the one of third pair ofterminals to the other. The third wiring is drawn on the grid G placedbetween the first wiring and the second wiring. One side of the thirdwiring faces only the first wiring, and one other side faces only thesecond wiring.

6) Three types of dummy wirings are drawn on the grid G where any of thefirst wiring, the second wiring and the third wiring are not drawn(hereinafter, referred to as open grid) (S26).

The first dummy wiring is drawn on the open grids along a first side ofthe third wiring. The first side surface of the third wiring faces thefirst wiring. The second dummy wiring is drawn on the grid G along asecond side of the third wiring. The second side surface of the thirdwiring faces the second wiring. There may be a plurality of first dummywirings and the second dummy wirings disposed along third wirings.

Next, another first dummy wiring is drawn on the open grids where anywiring is not drawn. For example, the first dummy wiring is drawn so asto be separated from other first dummy wiring via three or more grids.The first dummy wiring is drawn on the open grids separated from thesecond wiring or the second dummy wiring via one or more grids G. Thatis, the one or more grids G is interposed between the first dummy wiringand the second wiring or the second dummy wiring.

Another second dummy wiring is drawn so as to be separated from othersecond dummy wiring via three or more grids. Another second dummy wiringis drawn on the open grids separated from the first wiring or the firstdummy wiring via one or more grids G. The one or more grids G isinterposed between another second dummy wiring and the first wiring orthe first dummy wiring.

Next, at least one of the first wiring, the first dummy wiring, thesecond wiring and the second dummy wiring is expanded over the opengrids where any wiring is not drawn. In this case, an expanded part ofthe first wiring and an expanded part of the first dummy wiring aredrawn to be separated from one of the second wiring and the second dummywiring via one or more grids. The expanded parts of the first wiring andthe second wiring are regarded as parts of dummy wirings, respectively.

Subsequently, a third dummy wiring is drawn on open grids between thefirst wiring and one of the second wiring and the second dummy wiring,and between the first dummy wiring and one of the second wiring and thesecond dummy wiring. The third dummy wiring is drawn so as to bury allopen grids where any wiring is not drawn.

7) A mandrel mask pattern covering the first wiring and the first dummywiring, or the second wiring and the second dummy wiring is derived(S27).

8) A trimming mask pattern covering all dummy wirings is also derived(S28).

In the above procedure, the first wiring, the second wiring and thethird wiring are not limited to an example connecting between twoterminals, and may be drawn, for example, so as to go through a thirdterminal. The above process is executed, for example, by using a maskdesign system shown in FIG. 49. For example, the computer (i.e. thecontroller) displays the base grid on the display unit and drawsrespective wirings based on data inputted by a designer via an inputunit.

Next, a method of mask design will be more specifically described withreference to FIGS. 129 to 136. FIGS. 129 to 136 are schematic plan viewsillustrating a process of mask design.

A base grid 1100 shown in FIG. 129 is prepared (S21). The base grid 1100includes a plurality of grids G(m,n). The grids G are disposed, forexample, in 8×8 matrix configuration. Disposition pitch W_(p) of thegrids G is, for example, finally taken as a wiring pitch. Subsequently,a plurality of pairs of terminals A to D are disposed on the base grid1100 (S22).

As shown in FIG. 130, a first wiring 1101 is drawn to connect the pairof terminals A, and another first wiring 1103 is drawn to connect thepair of terminals B (S23). The first wiring 1103 is drawn so as to beseparated from the first wiring 1101 via three grids G. The first wiring1101 is drawn so as not to pass through the grids G where terminalsother than the pair of terminals A are disposed. The first wiring 1103is drawn so as not to pass through the grids where terminals other thanthe pair of terminals B are disposed.

Subsequently, a second wiring 1105 is drown to connect the pair ofterminals C (S24). The second wiring 1105 is drawn so as to be separatedfrom the first wirings 1101 and 1103 via one grid G. The second wiring1105 is drawn so as not to pass through the grids on which terminalsother than the pair of terminals C are disposed.

As shown in FIG. 131, a third wiring 1107 is drawn to connect the pairof terminals D (S25). The third wiring is drawn so as to pass throughgrids G between the first wiring 1101 and the second wiring 1105 andbetween the first wiring 1103 and the second wiring 1105. A first side1107 a of the third wiring 1107 faces the first wirings 1101 and 1103,but does not face the second wiring 1105. A second side 1107 b of thethird wiring 1107 faces the second wiring 1105, but does not face thefirst wirings 1101 and 1103. The third wiring 1107 is drawn so as not tohave a branch which provides a T-shaped part.

As shown in FIG. 132, a first dummy wiring 1113 and a second dummywiring 1115 are drawn (S26). The first dummy wiring 1113 is drawn onopen grids along the first side 1107 a of the third wiring 1107. Thesecond dummy wiring 1115 is drawn on open grids along the second side1107 b of the third wiring 1107.

Subsequently, the first dummy wiring and the second dummy wiring aredrawn on remaining open grids. The first dummy wiring is drawn so as tobe separated from the first wiring and other first dummy wiring viathree or more grids. The first dummy wiring is drawn on the open gridsseparated from the second wiring or the second dummy wiring via one ormore grids G. Thus, one or more grids G are interposed between the firstdummy wiring and the second wiring or the second dummy wiring.

The second dummy wiring is drawn so as to be separated from the secondwiring and other second dummy wiring via three or more grids. The seconddummy wiring is drawn on the open grids separated from the first wiringor the first dummy wiring via one or more grids G. One or more grids Gare interposed between the second dummy wiring and the first wiring orthe first dummy wiring.

In an example shown in FIG. 132, an open grid that satisfies theserestriction is only the open grid G(1, 8), when drawing a first dummywiring or a second dummy wiring. Then, the second dummy wiring 1117 isdrawn on the grid G(1,8).

As shown in FIG. 133, for example, the second dummy wiring 1115 isexpanded over the grid G(1,5) to grid G(1,7). The second wiring 1105 isexpanded over the grid G(8,1). Here, the second dummy wiring 1117 may beexpanded over the grid G(1,5) to grid G(1,7). A wiring expanded over thegrid G(8,1) is taken as a second dummy wiring 1119. The respectiveexpanded parts are separated from the first wirings 1101, 1103 and thefirst dummy wiring 1113 via one or more grids G.

The expanded part of the second wiring 1105 or the second dummy wiring1115 is drawn on an open grid located at a position separated from thefirst wirings 1103, 1105 and the first dummy wiring 1113 via one or moregrid G. In an example shown in FIG. 133, such an open grid is limited tothe grid G(1,5) to grid G(1,7) and the grid G(8,1).

When expanding the first wiring 1103 or the first dummy wiring 1113, theexpanded parts are drawn on an open grid located at a position separatedfrom the second wiring 1105, the second dummy wirings 1115 and 1117 viaone or more grid G.

As shown in FIG. 134, a third dummy wiring 1121 is drawn on an open gridremained after expanding the second wiring 1105 and the second dummywiring 1115. A first side 1121 a of the third dummy wiring 1121 facesthe first wirings 1101, 1103 and the first dummy wiring 1113. A secondside 1121 b of the third dummy wiring 1121 faces the second wiring 1105,the second dummy wirings 1115, 1117 and 1119. As shown in FIG. 134, therespective wirings are drawn so as to set a space between adjacentwirings to be equal.

As shown in FIG. 135, a mandrel mask pattern 1130 is derived (S27). Themandrel mask pattern 1130 covers the first wirings 1101, 1103 and thefirst dummy wiring 1113. A width of the mandrel mask pattern 1130 is,for example, set to be the same as a width of the pitch W_(p) of thegrid G. Alternatively, a mandrel mask pattern covering the second wiring1105, the second dummy wirings 1115, 1117 and 1119 may be derived.

As shown in FIG. 136, a trimming mask pattern 1140 is derived (S28). Thetrimming mask pattern 1140 covers the first dummy wiring 1113, thesecond dummy wirings 1115, 1117, 1119, and the third dummy wiring 1121.In other words, the trimming mask pattern 1140 covers all open grids.

Next, a method for manufacturing a semiconductor device using themandrel mask pattern 1130 and the trimming mask pattern 1140 will bedescribed with reference to FIGS. 137A to 141B. FIGS. 137A to 141B areschematic views illustrating a manufacturing process of a semiconductordevice according to the eleventh embodiment.

FIGS. 137A and 137B are schematic views showing a first mandrel 1160.FIG. 137A is a cross-sectional view along line 137A to 137A shown inFIG. 137B. FIG. 137B is a plan view showing the first mandrel 1160.

As shown in FIG. 137A, the first mandrel 1160 is formed, for example, onan interlayer insulating film 1150. The interlayer insulating film 1150is provided on a wafer not shown. As shown in FIG. 137B, the firstmandrel 1160 is formed using the mandrel mask pattern 1130.

FIGS. 138A to 138C are schematic views showing a first side wallprocess. FIGS. 138A to 138B are cross-sectional views along line 138B to138B shown in FIG. 138C. FIG. 137C is a plan view showing a first sidewall 1170.

As shown in FIG. 138A, the first side wall 1170 is formed on both sidesof the first mandrel 1160. The first mandrel 1160 is, for example,slimmed to be a prescribed width narrower than the width W_(p) of themandrel mask pattern 1130. After that, a first insulating film coveringthe first mandrel 1160 is formed. Subsequently, the first insulatingfilm is etched, for example, using RIE so that the first side wall 1170remains on a side surface of the first mandrel 1160. As shown in FIG.138C, the first side wall 1170 is formed along an outer periphery of thefirst mandrel 1160. Subsequently, as shown in FIG. 138B, the firstmandrel 1160 is selectively removed and the first side wall 1170 isremained on the interlayer insulating film 1150.

FIGS. 139A to 139C are schematic views showing a second side wallprocess. FIGS. 139A and 139B are cross-sectional views along line 139Bto 139B shown in FIG. 130C. FIG. 139C is a plan view showing a secondside wall 1190.

As shown in FIG. 139A, the second side wall 1190 is formed on both sidesof the first side wall 1170. The first side wall 1170 is used for asecond mandrel. The first side wall 1170 is slimmed, for example, to bea prescribed width. After that, a second insulating film is formed tocover the first side wall 1170. Subsequently, the second insulating filmis etched, for example, using RIE so that the second side wall 1190remains on a side surface of the first side wall 1170. As shown in FIG.139C, the second side wall 1190 is formed along an outer periphery ofthe first side wall 1170.

Subsequently, as shown in FIG. 139B, the first side wall 1170 isselectively removed and the second side wall 1190 is remained on theinterlayer insulating film 1150. Spaces between the second side walls1190 include a space where the first mandrel 1160 is removed, a spacewhere the first side wall 1170 is removed, and a space 1180 where bothof the first mandrel 1160 and the first side wall 1170 are not formed.

FIG. 140 is a schematic plan view showing a trimming mask 1195. Thetrimming mask 1195 is formed using the trimming mask pattern 1140.

As shown in FIG. 140, the trimming mask 1195 covers partially the secondside walls 1190 and the space between the second side walls. A part ofthe space where the first mandrel 1160 is removed, a part of the spacewhere the first side wall 1170 is removed, and a part of the space 1180are exposed in the open space not covered with the trimming mask 1195and the second side walls 1190.

FIGS. 141A and 141B are schematic views showing wirings formed using thesecond side walls 1190 and the trimming mask 1195. FIG. 141A is across-sectional view along line 141A to 141A shown in FIG. 141B.

As shown in FIG. 141A, the interlayer insulating film 1150 is etchedusing the second side walls 1190 and the trimming mask 1195 as anetching mask, and wiring grooves 1197 are formed. Subsequently, a wiringmetal 1200 is buried inside the wiring groove 1197 to form wirings of adamascene structure.

As shown in FIG. 141B, wirings can be formed corresponding to each ofthe first wirings 1101 and 1103, the second wiring 1105, and the thirdwiring 1107. The first wirings 1101 and 1103 are formed in the spacewhere the first mandrel 1160 is removed. The second wiring 1150 isformed in the space 1180 where both of the first mandrel 1160 and thefirst side wall 1170 are not formed. The third wiring 1107 is formed inthe space where the first side wall 1170 is removed. Furthermore, thefinal wiring pitch is formed to be the same as the pitch W_(p) of thegrid G.

According to the embodiment, terminal pairs may be disposed flexibly onthe base grid. Routing wirings for connecting terminals is lessrestricted. Therefore, the mask layout design may be improved so as tohave larger flexibility.

Next, a mask design method according to a variation of the embodimentwill be described with reference to FIGS. 142A to 153. FIGS. 142A to 153are schematic views showing the mask design method according to thevariation of the embodiment.

For example, the mask design can be made using layout parts 1210 to 1230shown in FIGS. 142A to 142C. Each layout part includes first wirings,second wirings, and third wirings. The first wirings, the secondwirings, and the third wirings are disposed in accordance with thepreviously described rule. That is, the first wirings are drawn so as tobe separated from each other via three or more grids G. The secondwirings are drawn so as to be separated from the first wirings via oneor more grids G. The third wirings are drawn on the grid G locatedbetween the first wirings and the second wirings. One side of the thirdwirings faces only the first wirings and another side faces only thesecond wirings.

As shown in FIG. 142A, the layout part 1210 includes the first wirings1211, 1213, 1215, the second wiring 1217, and the third wiring 1219. Inthis example, the first wiring 1211 and the first wiring 1215 are powersource lines. For example, the first wiring 1211 is a power source lineon High potential side, and the first wiring 1215 is a power source lineon Low potential side.

As shown in FIG. 142B, the layout part 1220 includes the first wirings1221, 1223, 1225, the second wiring 1227, and the third wiring 1229. Thefirst wiring 1221 is a power source line on High potential side, and thefirst wiring 1225 is a power source line on Low potential side.

As shown in FIG. 142C, the layout part 1230 includes the first wirings1231, 1233, 1235, the second wiring 1237, and the third wiring 1239. Thefirst wiring 1231 is a power source line on High potential side, and thefirst wiring 1235 is a power source line on Low potential side.

FIG. 143 shows a wiring layout 1300 where the layout parts 1210, 1220and 1230 are disposed on the base grid 1100. The layout parts 1210,1220, and 1230 are connected so as to share the power source lines onHigh potential side and on Low potential side.

In the example shown in FIG. 143, the second wiring 1227 of the layoutpart 1220 is disposed to face the second wiring 1237 of the layout part1230. Then, a space 1240 is interposed so as to separate the secondwiring 1227 from the second wiring 1237 via three or more grids G. Thespace 1240 includes three grids G in the X-direction.

Furthermore, the power source line of the layout part 1220 is connectedto the power source line of the layout part 1230. That is, the firstwiring 1241 is drawn in the space 1240. The first wiring 1241 connectsthe first wiring 1221 of the layout part 1220 and the first wiring 1231of the layout part 1230. The first wiring 1245 is drawn in the space1240. The first wiring 1245 connects the first wiring 1225 of the layoutpart 1220 and the first wiring 1235 of the layout part 1230. Thereby,the first wiring 1301 on High potential side and the first wiring 1305on Low potential side can be drawn on the base grid 1100.

Next, the first dummy wirings and the second dummy wirings are drawnalong the third wirings. For example, in the layout shown in FIG. 143,there is no first dummy wiring capable of being drawn along the thirdwirings with three or more grids G interposed between the first wiringsand itself. Then, as shown in FIG. 144, the second dummy wiring 1351along the third wiring 1219 and the second dummy wiring 1354 along thethird wiring 1229 are drawn.

Next, the first wirings or the second wirings are enlarged over opengrids on which no wiring is drawn. In this case, the first wirings areenlarged so as to be separated from the second wirings and the seconddummy wirings via one or more grids G in accordance with the previouslydescribed rule. The second wirings are enlarged so as to be separatedfrom the first wirings and the first dummy wirings via one or more gridsG.

In this example, an expanded part (hereinafter, second dummy wiring1353) is drawn between the second wiring 1227 and the second wiring 1327as shown in FIG. 145. In the following explanation, the expanded partsdrawn on multiple open grids arranged in series are described as thefirst dummy wirings or the second dummy wirings.

Subsequently, the expanded parts of the first wirings are drawn as shownin FIG. 146. The first dummy wiring 1311 is drawn between the firstwiring 1301 and the first wiring 1213. The first dummy wiring 1313 isdrawn between the first wiring 1305 and the first wiring 1213. The firstdummy wiring 1317 is drawn between the first wiring 1301 and the firstwiring 1223. The first dummy wiring 1319 is drawn between the firstwiring 1305 and the first wiring 1223.

Furthermore, the expanded parts 1321 and 1323 are drawn. The expandedpart 1321 is drawn on open grids between the first wiring 1301 and thesecond wiring 1227, between the first wiring 1301 and the second dummywiring 1353, between the first wiring 1301 and the second wiring 1237,and between the first wiring 1301 and the first wiring 1233. Theexpanded part 1323 is drawn on open grids between the first wiring 1305and the second dummy wiring 1354, between the first wiring 1305 and thesecond dummy wiring 1353, between the first wiring 1305 and the secondwiring 1237, and between the first wiring 1305 and the first wiring1233.

Next, as shown in FIG. 147, the third dummy wirings 1361, 1363 and 1365are drawn, and thus, the wiring layout 1300 is completed.

The third dummy wiring 1361 is drawn on open grids between the firstwiring 1305 and the second dummy wiring 1351, between the first dummywiring 1319 and the second dummy wiring 1351, between the first wiring1223 and the second wiring 1217, and between the first dummy wiring 1317and the second wiring 1217.

The third dummy wiring 1363 is drawn on open grids between the firstdummy wiring 1317 and the second wiring 1227, between the first wiring1301 and the second wiring 1227, between the expanded part 1321 and thesecond dummy wiring 1353, and between the expanded part 1321 and thesecond wiring 1237. The third dummy wiring 1365 is drawn on open gridsbetween the expanded part 1323 and the second dummy wiring 1353, andbetween the expanded part 1323 and the second dummy wiring 1254.

Next, the first wirings and the first dummy wirings or the secondwirings and the second dummy wirings are extracted as a core pattern.Furthermore, a trim mask covering the first dummy wirings, the seconddummy wirings and the expanded parts is extracted and the mask design iscompleted.

FIGS. 148A to 148C show other combination of layout parts. The layoutpart 1210 shown in FIG. 148A, the layout part 1220 shown in FIG. 148B,and the layout part 1250 shown in FIG. 148C are used in this example.The layout part 1250 includes the first wirings 1251, 1253, 1255, thesecond wiring 1257 and the third wiring 1259. The first wiring 1251 andthe first wiring 1255 are, for example, power source lines.

FIG. 149 shows a wiring layout 1400 where the lay out parts 1210, 1220and 1250 are disposed on the base grid 1100. The layout parts 1210, 1220and 1250 are connected so as to share the power source lines on Highpotential side and on Low potential side.

In the example shown in FIG. 149, the second wiring 1227 of the layoutpart 1220 faces the first wiring 1253 of the layout part 1250. Then, thespace 1260 is interposed so as to separate the second wiring 1227 fromthe first wiring 1253 via one or more grids G.

The space 1260 includes one grid G in the X-direction. The first wirings1261 and 1265 are drawn on the space 1260. The first wiring 1261connects the first wiring 1221 of the layout part 1220 and the firstwiring 1251 of the layout part 1250. The first wiring 1265 connects thefirst wiring 1225 of the lay out part 1220 and the first wiring 1255 ofthe lay out part 1250. Thereby, the first wirings 1401 and 1405 aredrawn on the base grid 1100.

Subsequently, the first dummy wirings and the second dummy wirings aredrawn in accordance with the previously described rule. Then, the firstwirings and the first dummy wirings, or the second wirings and thesecond dummy wirings are expanded. Furthermore, the third dummy wiringsare drawn, and a wiring layout 1400 is completed as shown in FIG. 150.

In this example, the second dummy wiring 1451 is drawn along the thirdwiring 1219. The second dummy wirings 1453 and 1355 are drawn along thethird wirings 1229 and 1259.

Furthermore, the second dummy wirings 1453 and 1455 are expanded so asto surround the first wiring 1253. The first wiring 1401 and the firstwiring 1405 are expanded, and the first dummy wirings 1411, 1413, 1417,and 1419 are drawn. The third dummy wirings 1461, 1463, and 1465 aredrawn, and the wiring layout 1400 is completed.

Here, the number of grids arranged in a lateral direction is 11 in thelayout of FIG. 149. In contrast, the number of grids arranged in alateral direction is 13 in the layout of FIG. 143. That is, the firstwirings 1233 and 1253 are inversely disposed in the lateral directionbetween the layout in FIG. 142C and the layout in FIG. 148C. Then, sucharrangements make a lateral width of the space 1260 narrower than thatof the space 1240.

FIGS. 151A to 151C show other combination of layout parts. The layoutpart 1210 shown in FIG. 151A, the layout part 1220 shown in FIG. 151B,and the layout part 1270 shown in FIG. 151C are used in this example.The layout part 1270 includes the first wirings 1271, 1273, 1275, thesecond wiring 1227 and the third wiring 1279. The first wiring 1271 andthe first wiring 1275 are, for example, power source lines.

FIG. 152 shows a wiring layout 1500 where the layout parts 1210, 1220,and 1270 are disposed on the base grid 1100. The layout parts 1210, 1220and 1270 are connected so as to share the power source lines on Highpotential side and on Low potential side.

In this example, the second wiring 1227 of the layout part 1220 facesthe first wiring 1273 of the layout part 1270. Then, the space 1260 isinterposed so as to separate the second wiring 1227 from the firstwiring 1273 via one or more grids G.

The space 1260 includes one grid G in the X-direction. The first wirings1261 and 1265 are drawn on the space 1260. The first wiring 1261connects the first wiring 1221 of the layout part 1220 and the firstwiring 1271 of the layout part 1270. The first wiring 1265 connects thefirst wiring 1225 of the layout part 1220 and the first wiring 1275 ofthe layout part 1270. Thereby, the first wirings 1501 and 1505 are drawnon the base grid 1100.

Subsequently, the first dummy wirings and the second dummy wirings aredrawn in accordance with the previously described rule. Then, the firstwirings and the first dummy wirings, or the second wirings and thesecond dummy wirings are expanded. Furthermore, the third dummy wiringsare drawn, and the wiring layout 1500 is completed as shown in FIG. 153.

In this example, the second dummy wiring 1551 is drawn along the thirdwiring 1219. The second dummy wiring 1553 is drawn along the thirdwiring 1229.

Furthermore, the first wiring 1501 and the first wiring 1505 areexpanded, and the first dummy wirings 1511, 1513, 1517, 1519, and theexpanded parts 1521, 1523 are drawn. The third dummy wirings 1561, 1563,1565, and 1567 are drawn, and the wiring layout 1500 is completed.

Here, the number of grids arranged in a lateral direction is 11 in thelayout of FIG. 152. In contrast, the number of grids arranged in alateral direction is 13 in the layout of FIG. 143. That is, reversingthe layout parts makes a lateral width of the space 1260 narrower thanthat of the space 1240 as shown in FIG. 151C and FIG. 148C.

According to the embodiments explained above, it is possible to providea method for designing a wiring layout capable of aiming at a highdegree of integration, a semiconductor device, a program for supportinga design of a wiring layout, and a method for manufacturing asemiconductor device.

It is also possible to combine an automatic wiring method represented byan algorithm, such as a maze method, with the embodiments. As a resultof that, it is possible to perform automatic wiring of a pattern capableof being subjected to wiring formed by the sidewall method. As a resultof that, it is possible to further improve the design efficiency.

In the embodiments described above, the descriptions have been made sothat the red, blue and green correspond to the wirings different fromeach other, for convenient, and it may be possible to implement a methodfor distinguishing the wirings other than color method.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the invention.

What is claimed is:
 1. A design method of a mask pattern, the methodcomprising: providing a base pattern including a plurality of firstcells, a plurality of second cells, and a plurality of blank cells, thebase pattern including first columns, second columns, first rows, andsecond rows, the first columns and the second columns each including aplurality of cells aligned in a first direction, and being alternatelyarranged in a second direction orthogonal to the first direction, andthe first rows and the second rows each including a plurality of cellsaligned in the second direction, and being alternately arranged in thefirst direction, wherein the plurality of first cells are disposed atcross points of the first columns and the first rows respectively, theplurality of second cells are disposed at cross points of the secondcolumns and the second rows respectively, and the plurality of blankcells are disposed in the first direction and the second directionbetween the plurality of first cells and between the plurality of secondcells; assigning a start first cell and an end first cell in theplurality of first cells; providing first patterns on blank cells of theplurality of blank cells respectively, the first patterns eachconnecting two adjacent first cells of the plurality of first cells inthe first or second direction, and being disposed to make a pathway fromthe start first cell to the end first cell; assigning a start secondcell and an end second cell in the plurality of second cells; providingsecond patterns on blank cells of the plurality of blank cellsrespectively, the second patterns each connecting two adjacent secondcells of the plurality of second cells in the first or second directionwithout overlapping the first patterns, and being disposed to making apathway from the start second cell to the end second cell; andextracting a first group or a second group to make the mask pattern, thefirst group including the first patterns and the first cells connectedby the first patterns, and the second group including the secondpatterns and the second cells connected by the second patterns.
 2. Themethod according to claim 1, further comprising: providing extra firstpatterns on blank cells of the plurality of blank cells, the extra firstpatterns each connecting two adjacent first cells of the plurality offirst cells in the first or second direction without overlapping thefirst patterns and the second patterns, and no one of the extra firstpatterns being connected to the first cells connected by the firstpatterns; and providing extra second patterns on blank cells of theplurality of blank cells, the extra second patterns each connecting twoadjacent second cells of the plurality of second cells in the first orsecond direction without overlapping the first patterns, the secondpatterns, and the extra first patterns, and no one of the extra secondpatterns being connected to the second cells connected by the secondpatterns, wherein the first group further includes the extra firstpatterns and the first cells connected by the extra first patterns, andthe second group further includes the extra second patterns and thesecond cells connected by the extra second patterns.
 3. The methodaccording to claim 1, further comprising: providing extra secondpatterns on blank cells of the plurality of blank cells, the extrasecond patterns each connecting two adjacent second cells of theplurality of second cells in the first or second direction withoutoverlapping the first patterns and the second patterns, and no one ofthe extra second patterns being connected to the second cells connectedby the second patterns; and providing extra first patterns on blankcells of the plurality of blank cells, the extra first patterns eachconnecting two adjacent first cells of the plurality of first cells inthe fow or column first or second direction without overlapping thefirst patterns, the second patterns and the extra second patterns, andno one of the extra first patterns being connected to the first cellsconnected by the first patterns, wherein the first group furtherincludes the extra first patterns, and the second group further includesthe extra second patterns.
 4. The method according to claim 1, furthercomprising: providing a trimming pattern covering the first patterns,the first cells connected by the first patterns, the second patterns andthe second cells connected by the second patterns.
 5. The methodaccording to claim 4, wherein the trimming pattern further covers one ofa first cell and a second cell, no one of a first pattern and a secondpattern being connected to the one of a first cell and a second cell,and the one of a first pattern and a second pattern being surrounded byfirst cells and first patterns connected thereto, or second cells andsecond patterns connected thereto; and/or the trimming pattern furthercovers a blank cell, no one of a first pattern and a second patternbeing provided on the blank cell, and the blank cell being surrounded byfirst cells and first patterns connected thereto, or by second cells andsecond patterns connected thereto.
 6. The method according to claim 2,further comprising: providing a cutout part without overlapping any oneof the first patterns, the second patterns, the extra first patterns,and the extra second patterns, the cutout part being disposed on a blankcell positioned between a first cell, to which one of the first patternsis connected, and another first cell, to which one of the extra firstpatterns is connected, when the first group is to be extracted, and thecutout part being provided not to connect the first cell to the anotherfirst cell; and providing a cutout part without overlapping any one ofthe first patterns, the second patterns, the extra first patterns, andthe extra second patterns, the cutout part being disposed on a blankcell positioned between a second cell, to which one of the secondpatterns is connected, and another second cell, to which one of theextra second patterns is connected, when the second group is to beextracted, and the cutout part being provided not to connect the secondcell to the another second cell.
 7. The method according to claim 6,further comprising: providing another cutout part without overlappingany one of the first patterns, the second patterns, the extra firstpatterns, and the extra second patterns, the another cutout part beingdisposed on a blank cell positioned between a first cell, to which oneof the first patterns is connected, and another first cell, to which noone of the first patterns and the extra first patterns is connected, orbetween a second cell, to which one of the second patterns is connected,and another second cell, to which no one of the second patterns and theextra second patterns is connected, and the another cutout part beingprovided not to connect the first cell to the another first cell, or thesecond cell to the another second cell.
 8. A design method of a maskpattern, the method comprising: providing a base pattern including aplurality of first cells, a plurality of second cells, a plurality ofthird cells, a plurality of first blank cells, a plurality of secondblank cells, and a plurality of third blank cells, the base patternincluding first columns, second columns, third columns, first rows,second rows, and third rows, the first to third columns each including aplurality of cells aligned in a first direction, the first columns andthe second columns being alternately arranged in a second directionorthogonal to the first direction, each of the third columns beingdisposed between one of the first columns and one of the second columnsadjacent to each other in the second direction, the first to third rowseach including a plurality of cells aligned in the second direction, thefirst rows and the second rows being alternately arranged in the firstdirection, and each of the third rows being disposed between one of thefirst rows and one of the second rows adjacent to each other in thefirst direction, wherein the plurality of first cells are disposed atcross points of the first columns and the first lows, respectively, theplurality of second cells are disposed at cross points of the secondcolumns and the second rows, respectively, the plurality of third cellsare disposed at cross points of the third columns and third rows,respectively, the plurality of first blank cells are disposedrespectively between the plurality of first cells in the first andsecond directions and between the plurality of second cells in the firstand second directions, each of the plurality of second blank cells isdisposed between a first cell of the plurality of first cells and afirst blank cell of the plurality of first blank cells adjacent to eachother in the first and second direction, and each of the plurality ofthird blank cells is disposed between a second cell of the plurality ofsecond cells and a first blank cell of the plurality of first blankcells adjacent to each other in the first or second direction; assigninga start first cell and an end first cell in the plurality of firstcells; providing first patterns each extending over a first blank cellof the plurality of first blank cells and two second blank cellsadjacent to the first blank cell, the first patterns each connecting twoadjacent first cells of the plurality of first cells in the first orsecond direction, and being disposed to make a pathway from the startfirst cell to the end first cell; assigning a start second cell and anend second cell in the plurality of second cells; providing secondpatterns each extending over a first blank cell of the plurality offirst blank cells and two third blank cells adjacent to the first blankcell, the second patterns each connecting two adjacent second cells ofthe plurality of second cells in the first or second direction withoutoverlapping the first patterns, and being disposed to making a pathwayfrom the start second cell to the end second cell; assigning a startthird cell and an end third cell in the plurality of third cells;providing third patterns each disposed on a second blank cell of theplurality of second blank cells or a third blank cell of the pluralityof third blank cells, the third patterns each connecting two adjacentthird cells of the plurality of third cells in the first or seconddirection without overlapping any one of the first patterns and thesecond patterns, and being disposed to making a pathway from the startthird cell to the end third cell; and extracting a first group or asecond group to make the mask pattern, the first group including thefirst patterns and the first cells connected by the first patterns, andthe second group including the second patterns and the second cellsconnected by the second patterns.
 9. The method according to claim 8,wherein no third pattern is disposed such that one of the plurality offirst blank cells locates at a position adjacent to two third patternsconnected to one of the plurality of third cells in the second directionand the first direction respectively.
 10. The method according to claim8, further comprising: providing extra first patterns each extendingover a first blank cell of the plurality of first blank cells and twosecond blank cells adjacent to the first blank cell, the extra firstpatterns each connecting two adjacent first cells of the plurality offirst cells in the first or second direction without overlapping any oneof the first patterns, the second patterns, and the third patterns, andno one of the extra first patterns being connected to the first cellsconnected by the first patterns; providing extra second patterns eachextending over a first blank cell of the plurality of first blank cellsand two third blank cells adjacent to the first blank cell, the extrasecond patterns each connecting two adjacent second cells of theplurality of second cells in the first or second direction withoutoverlapping the first patterns, the second patterns, the third patterns,and the extra first patterns, and no one of the extra second patternsbeing connected to the second cells connected by the second patterns;and providing extra third patterns each provided on a second blank cellof the plurality of second blank cells or a third blank cell of theplurality of third blank cells, the extra third patterns each connectingtwo adjacent third cells of the plurality of third cells in the first orsecond direction without overlapping any one of the first patterns, thesecond patterns, the third patterns, the extra first patterns, and theextra second patterns, wherein the first group further includes theextra first patterns and the first cells connected by the extra firstpattern, and the second group further includes the extra second patternsand the second cells connected by the extra second pattern.
 11. Themethod according to claim 10, further comprising: providing a cutoutpart without overlapping any one of the first patterns, the secondpatterns, the third patterns, the extra first patterns, the extra secondpatterns, and the extra third patterns, the cutout part being disposedon one of a first blank cell and two second blank cells, the first blankcell and the two second blank cells being positioned between a firstcell, to which one of the first patterns is connected, and another firstcell, to which one of the extra first patterns is connected, when thefirst group is to be extracted, and the cutout part being provided notto connect the first cell to the another first cell; and providing acutout part without overlapping any one of the first patterns, thesecond patterns, the third patterns, the extra first patterns, the extrasecond patterns, and the extra third patterns, the cutout part beingdisposed on one of a first blank cell and two third blank cells, thefirst blank cell and the two third blank cells being positioned betweena second cell, to which one of the second patterns is connected, andanother second cell, to which one of the extra second patterns isconnected, when the second group is to be extracted, and the cutout partbeing provided not to connect the second cell to the another secondcell.
 12. A design method of mask patterns, the method comprising:providing a base pattern including a plurality of first cells, aplurality of second cells, a plurality of third cells, and a pluralityof blank cells, the base pattern including first columns, secondcolumns, third columns, first rows, second rows, and third rows, thefirst to third columns each including a plurality of cells aligned in afirst direction, the first columns and the second columns beingalternately arranged in a second direction orthogonal to the firstdirection, each of the third columns being disposed between one of thefirst columns and one of the second columns adjacent to each other inthe second direction, the first to third rows each including a pluralityof cells aligned in the second direction, the first rows and the secondrows being alternately arranged in the first direction, and each of thethird rows being disposed between one of the first rows and one of thesecond rows adjacent to each other in the first direction, wherein theplurality of first cells are disposed at cross points of the firstcolumns and the first lows, respectively, the plurality of second cellsare disposed at cross points of the second columns and the second rows,respectively, the plurality of third cells are disposed at cross pointsof the third columns and third rows, respectively, the plurality ofblank cells are disposed respectively between the plurality of firstcells in the first direction and the second direction, between theplurality of second cells in the first direction and the seconddirection, and between the plurality of third cells in the firstdirection and the second direction; assigning a start third cell and anend third cell in the plurality of third cells; providing third patternsdisposed on blank cells of the plurality of blank cells respectively,the third patterns each connecting two adjacent third cells of theplurality of third cells in the first or second direction, and beingdisposed to make a pathway from the start third cell to the end thirdcell; providing first patterns each extending over blank cells of theplurality of blank cells positioned between two adjacent first cells ofthe plurality of first cells in the first or second direction, the firstpatterns each connecting the two adjacent first cells withoutoverlapping the third patterns; providing second patterns each extendingover blank cells of the plurality of blank cells positioned between twoadjacent second cells of the plurality of second cells in the first orsecond direction, the second patterns each connecting the two adjacentsecond cells without overlapping the first patterns and the thirdpatterns; and extracting a first group or a second group to make themask pattern, the first group including the first patterns and the firstcells connected by the first patterns, and the second group includingthe second patterns and the second cells connected by the secondpatterns.
 13. The method according to claim 12, wherein the thirdpatterns are disposed such that no one of the plurality of blank cellsis located at a position adjacent to two third patterns connected to oneof the plurality of third cells, one of the two third pattern beingconnected to the one of the plurality of third cells in the seconddirection, and the other of the two third pattern being connected to theone of the plurality of third cells in the first direction.
 14. Themethod according to claim 12, further comprising: providing extra thirdpatterns each provided on a blank cell of the plurality of blank cells,the extra third patterns each connecting two adjacent third cells of theplurality of third cells in the first or second direction withoutoverlapping any one of the first patterns, the second patterns, and thethird patterns; and providing a trimming pattern covering the extrathird patterns.
 15. The method according to claim 12, furthercomprising: assigning a start first cell and an end first cell in theplurality of first cells; and assigning a start second cell and an endsecond cell in the plurality of second cells, wherein the first patternsare disposed to make a pathway from the start first cell to the endfirst cell, and the second patterns are disposed to make a pathway fromthe start second cell to the end second cell.
 16. The method accordingto claim 15, further comprising: providing extra first patterns eachextending over blank cells between two adjacent first cells of theplurality of first cells, the extra first patterns each connecting thetwo adjacent first cells in the first or second direction withoutoverlapping any one of the first patterns, the second patterns, and thethird patterns, and no one of the extra first patterns being connectedto the first cells connected by the first patterns; providing extrasecond patterns each extending over blank cells between two adjacentsecond cells of the plurality of second cells, the extra second patternseach connecting the two adjacent second cells in the first or seconddirection without overlapping the first patterns, the second patterns,the third patterns, and the extra first patterns, and no one of theextra second patterns being connected to the second cells connected bythe second patterns; and providing extra third patterns each provided ona blank cell of the plurality of blank cells, the extra third patternseach connecting two adjacent third cells of the plurality of third cellsin the first or second direction without overlapping any one of thefirst patterns, the second patterns, the third patterns, the extra firstpatterns, and the extra second patterns, and no one of the extra thirdpatterns being connected to the third cells connected by the thirdpatterns.
 17. The method according to claim 15, further comprising:providing a cutout part without overlapping any one of the firstpatterns, the second patterns, the third patterns, the extra firstpatterns, the extra second patterns, and the extra third patterns, thecutout part being disposed on a blank cell positioned between a firstcell, to which one of the first patterns is connected, and another firstcell, to which one of the extra first patterns is connected, when thefirst group is to be extracted, and the cutout part being provided notto connect the first cell to the another first cell; and providing acutout part without overlapping any one of the first patterns, thesecond patterns, the third patterns, the extra first patterns, the extrasecond patterns, and the extra third patterns, the cutout part beingdisposed on a blank cell positioned between a second cell, to which oneof the second patterns is connected, and another second cell, to whichone of the extra second patterns is connected, when the second group isto be extracted, and the cutout part being provided not to connect thesecond cell to the another second cell.
 18. A design method of maskpatterns, the method comprising: providing a base pattern including aplurality of blank cells disposed in a plurality of columns, each of theplurality of columns including blank cells aligned in a first direction,and the plurality of columns being arranged in a second directionorthogonal to the first direction; assigning a plurality of pairs ofstart and end cells on the base pattern, the plurality of pairs of startand end cells including first to third start cells and first to thirdend cells each assigned on a blank cell of the plurality of blank cells;providing a first interconnection connecting a first start cell and afirst end cell by disposing first patterns on blank cells of theplurality of blank cells respectively; providing other firstinterconnection connecting other first start cell and other first endcell by disposing other first patterns on blank cells of the pluralityof blank cells respectively, the other first interconnection beingseparated from the first interconnection with a distance equal to ormore than a length of three blank cells arranged in series; providing asecond interconnection connecting a second start cell and a second endcell by disposing second patterns on blank cells of the plurality ofblank cells respectively, the second interconnection being separatedfrom the first interconnection and the other first interconnection witha distance equal to or more than a length of one blank cell; providing athird interconnection connecting a third start cell and a third end cellof the plurality of pairs by disposing third patterns on blank cells ofthe matrix respectively, the third interconnection extending between thefirst interconnection and the second interconnection and/or between theother first interconnection and the second interconnection; andextracting a first group of interconnections or a second group ofinterconnections to make the mask pattern, the first group including thefirst interconnection and the other first interconnection, and thesecond group including the second interconnection.
 19. The methodaccording to claim 18, further comprising: providing other secondinterconnection connecting other second start cell and other second endcell by disposing other second patterns on blank cells of the pluralityof blank cells respectively, the other second interconnection beingseparated from the second interconnection with a distance equal to ormore than a length of three blank cells arranged in series.
 20. Themethod according to claim 18, wherein: the third interconnection has afirst side and a second side, the first side facing the firstinterconnection and/or the other first interconnection, and the secondside facing the second interconnection.
 21. The method according toclaim 20, further comprising: providing an extra first interconnectionby disposing extra first patterns respectively on blank cells positionedalong the first side of the third interconnection; and providing anextra second interconnection by disposing extra second patternsrespectively on blank cells positioned along the second side of thethird interconnection.
 22. The method according to claim 21, furthercomprising: providing at least one of an other extra firstinterconnection and an other extra second interconnection, wherein theother extra first interconnection is formed by disposing other extrafirst patterns on blank cells of the plurality of blank cellsrespectively, the other extra first interconnection being separated fromthe first interconnection, the other first interconnection and the extrafirst interconnection with a distance equal to or more than a length ofthree blank cells arranged in series, and being separated from thesecond interconnection and the extra second interconnection with adistance equal to or more than a length of one blank cell, and the otherextra second interconnection is formed by disposing other extra secondpatterns on blank cells of the plurality of blank cells respectively,the other extra second interconnection being separated from the secondinterconnection and the extra second interconnection with a distanceequal to or more than a length of three blank cells arranged in series,and being separated from the first interconnection, the other firstinterconnection and the extra first interconnection with a distanceequal to or more than a length of one blank cell; extending at least oneof the first interconnection, the other first interconnection, the extrafirst interconnection, the other extra first interconnection, the secondinterconnection, the extra second interconnection, and the other extrasecond interconnection over blank cells capable of extending thereover;and providing at least one of extra third interconnections to fill allof blank cells in the plurality of blank cells, the extra thirdinterconnections being formed by disposing extra third patterns on blankcells of the plurality of blank cells respectively.
 23. The methodaccording to claim 22, further comprising: providing a trimming patterncovering part of the plurality of blank cells other than the firstinterconnection, the other first interconnection, the secondinterconnection, and the third interconnection.
 24. The method accordingto claim 23, wherein the trimming pattern further covers the extendedparts of the first interconnection, the other first interconnection andthe second interconnection.
 25. The method according to claim 18,further comprising: providing a plurality of sub-base patterns eachincluding a part of the plurality of blank cells, wherein the pluralityof pairs are assigned on the plurality of sub-base patterns, and thefirst to third interconnections are provided on the plurality ofsub-base patterns.
 26. The method according to claim 18, wherein an areaof the mask pattern is reduced by interchanging one of the firstinterconnections with one of the second interconnections.
 27. A methodfor manufacturing a semiconductor device, the method comprising: forminga first layer on a semiconductor substrate; forming a second layer onthe first layer; forming a core member on the first layer by selectivelyremoving the second layer; forming a side wall around the core member onthe first layer, the side wall being provided on a side surface of thecore member; removing the core member so that the side wall remains onthe first layer; and selectively removing the first layer using the sidewall as an etching mask, wherein the second layer is selectively removedusing a mask pattern designed by a method comprising: providing a basepattern including a plurality of first cells, a plurality of secondcells and a plurality of blank cells, the base pattern including firstcolumns, second columns, first rows, and second rows, the first columnsand the second columns each including a plurality of cells aligned in afirst direction, and being alternately arranged in a second directionorthogonal to the first direction, and the first rows and the secondrows each including a plurality of cells aligned in the seconddirection, and being alternately arranged in the first direction,wherein the plurality of first cells are disposed at cross points of thefirst columns and the first rows respectively, the plurality of secondcells are disposed at cross points of the second columns and the secondrows respectively, and the plurality of blank cells are disposed in thefirst direction and the second direction between the plurality of firstcells and between the plurality of second cells; assigning a start firstcell and an end first cell in the plurality of first cells; providingfirst patterns on blank cells of the plurality of blank cellsrespectively, the first patterns each connecting two adjacent firstcells of the plurality of first cells in the first or second direction,and being disposed to make a pathway from the start first cell to theend first cell; assigning a start second cell and an end second cell inthe plurality of second cells; providing second patterns on blank cellsof the plurality of blank cells respectively, the second patterns eachconnecting two adjacent second cells of the plurality of second cells inthe first or second direction without overlapping the first patterns,and being disposed to making a pathway from the start second cell to theend second cell; and extracting a first group or a second group to makethe mask pattern, the first group including the first patterns and thefirst cells connected by the first patterns, and the second groupincluding the second patterns and the second cells connected by thesecond patterns.